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Liu J.,CAS Changchun Institute of Applied Chemistry | Liu J.,University of Chinese Academy of Sciences | Song P.,CAS Changchun Institute of Applied Chemistry | Xu W.,CAS Changchun Institute of Applied Chemistry
Carbon | Year: 2017

Resolving the structure-activity relationship of doped-nitrogen (N)-based active sites on carbon and their variation mechanism during oxygen reduction reaction (ORR) process have been very desirable for the deep understanding of doped-N-based carbon materials. Here, by correlating the ORR catalytic performance with chemical compositions of N-doped carbon samples and performing systematic quantum chemical calculations, we partially resolved the structure-activity relationship of different N-containing active sites on N-doped carbon, including the ORR-induced transformation of both pyridinic and graphitic N to pyrrolic N, the revealing of the catalytic activity order of different N-containing sites for ORR from both experimental and theoretical points of view systematically: pyridinic N > pyrrolic N > graphitic N > oxidized N > C (carbon). The tiny structure difference-induced huge ORR activity difference of N-containing sites was also revealed. All these new understandings to the doped-N-based ORR carbon catalysts can guide the rational design of N-doped metal-free catalysts. © 2017


Liu Z.,Jilin University | Ma Q.,Jilin University | Wang X.,CAS Changchun Institute of Applied Chemistry | Lin Z.,Jilin University | And 3 more authors.
Biosensors and Bioelectronics | Year: 2014

In this work, a novel fluorescence "turn off-on" nanosensor for the determination of heparin and heparinase based on CuInS2 quantum dots (QDs) was established. CuInS2 QDs (modified by l-cysteine) featuring amino groups were directly prepared in aqueous solution via a hydrothermal synthesis method. The amino groups on the surface of CuInS2 QDs can interact with sulfate and carboxylate groups in heparin via electrostatic interactions and hydrogen bonding, which led the fluorescence of CuInS2 QDs to "turn-off". However, the heparin could be hydrolyzed into small fragments in the presence of heparinase, which resulted in the fluorescence of CuInS2 QDs being recovered. Therefore, the addition of heparinase to the heparin/CuInS2 QDs system activated the fluorescence of CuInS2 QDs to "turn-on" state. Thus, the determination of heparin and heparinase could be achieved by monitoring the fluorescence "turn off-on". Under the optimum conditions, there was a good linear relationship between I/I0 (I and I0 were the fluorescence intensity of CuInS2 QDs in the presence and absence of heparin, respectively) and heparin concentration in the range of 0.05-15μmolL-1 with the detection limit of 12.46nmolL-1. The linear detection for heparinase was in the range of 0.2-5μgmL-1 with the detection limit of 0.07μgmL-1. The proposed nanosensor was employed for the detection of heparin in fetal bovine serum samples with satisfactory results. © 2013 Elsevier B.V.


Liu B.,CAS Changchun Institute of Applied Chemistry | Li C.,Zhejiang Normal University | Yang P.,Harbin Engineering University | Hou Z.,CAS Changchun Institute of Applied Chemistry | Lin J.,CAS Changchun Institute of Applied Chemistry
Advanced Materials | Year: 2017

808 nm-light-excited lanthanide (Ln3+)-doped nanoparticles (LnNPs) hold great promise for a wide range of applications, including bioimaging diagnosis and anticancer therapy. This is due to their unique properties, including their minimized overheating effect, improved penetration depth, relatively high quantum yields, and other common features of LnNPs. In this review, the progress of 808 nm-excited LnNPs is reported, including their i) luminescence mechanism, ii) luminescence enhancement, iii) color tuning, iv) diagnostic and v) therapeutic applications. Finally, the future outlook and challenges of 808 nm-excited LnNPs are presented. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,CAS Changchun Institute of Applied Chemistry | Komarneni S.,Pennsylvania State University
Journal of Colloid and Interface Science | Year: 2017

Nanoclay assisted electrochemical exfoliation was developed to in-situ form functionalized graphene electrode materials from pencil core with different ratios of graphite and clay. This method made a positive transformation from solid graphite to graphene colloidal solution, which can be used to construct binder- and additive-free thin-film electrodes. Exfoliated graphene can be served as both conductive current collector (film resistance of 33 Ω/square) and electrode materials. Graphene thin-film electrodes from pencil cores displayed higher capacity of 224 than 80 mA h/g of that from pure graphite. The electrochemical performance can be controlled by the ratio of graphite and clay and the oxidation reaction of surface oxygen functional groups. The described nanoclay-assisted electrochemical oxidation route shows great potential for the synthesis of functionalized graphene electrode materials for high-conductive thin-film lithium ion batteries and supercapacitors. © 2016 Elsevier Inc.


Wang L.,CAS Changchun Institute of Applied Chemistry | Xie Z.,CAS Changchun Institute of Applied Chemistry | Dang S.,CAS Changchun Institute of Applied Chemistry | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry
Chemistry - A European Journal | Year: 2017

A series of heterometallic lanthanide (Ln)-Ru coordination polymers, denoted Gd-1, Yb-2, and Nd-3, were prepared by solvothermal reaction of a carboxylate derivative of [Ru(bpy)3]2+ (Rubpy, bpy=2,2′-bipyridine), oxalic acid, and Ln(OAc)3 by using the metalloligand strategy. Single-crystal X-ray diffraction indicated that the resulting isostructural heterometallic complexes have 1D butterfly-shaped Ln-Ru-based coordination chains but show slight differences in the coordination environments of the Ln centers. The introduced Ru(bpy) metalloligands could act as good light-harvesting antennas to effectively sensitize near-infrared (NIR) luminescence by energy transfer from the triplet metal-to ligand charge transfer state of Rubpy units to Ln (Yb or Nd) under the excitation in the visible-light region. Additionally, dopant-concentration-dependent behavior of the Ru-based emission and sensitized NIR emission was demonstrated in Gd-1. Finally, the magnetocaloric effect of Gd-1 was studied. The preparation of such heterometallic coordination polymers offers a versatile platform to investigate dimensionally controlled properties. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu B.,CAS Changchun Institute of Applied Chemistry | Liu B.,Jilin University | Li S.,CAS Changchun Institute of Applied Chemistry | Wang M.,CAS Changchun Institute of Applied Chemistry | Cui D.,CAS Changchun Institute of Applied Chemistry
Angewandte Chemie - International Edition | Year: 2017

Coordination polymerization of renewable 3-methylenecyclopentene has been investigated for the first time using rare-earth metal-based precursors bearing various bulky ligands. All the prepared complexes catalyze controllable polymerization of 3-methylenecyclopentene into high molecular weight polymers, of which the NPN- and NSN-tridentate non-Cp ligated lutetium-based catalytic systems exhibited extremely high activities up to 11 520 kg/(molLu⋅h) in a dilute toluene solution (3.2 g/100 mL) at room temperature. The resultant polymers have pure 1,4-regioregularity (>99 %) and tailorable number average molecular weights (1–20×104) with narrow molecular weight distributions (polydispersity index (PDI)=1.45–1.79). DFT simulations were employed to study the polymerization mechanism and stereoregularity control. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim


Fang X.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook
Physical Biology | Year: 2017

Cellular networks have been the focus of studies in modern systems biology. They are crucial in understanding cell functions and related diseases. We review some past progress in both the theory and experiments, and we also provide several future perspectives for the field. © 2017 IOP Publishing Ltd.


Chen J.,CAS Changchun Institute of Applied Chemistry | Guo Z.,CAS Changchun Institute of Applied Chemistry | Tian H.,CAS Changchun Institute of Applied Chemistry | Chen X.,CAS Changchun Institute of Applied Chemistry
Molecular Therapy - Methods and Clinical Development | Year: 2016

Gene therapy is a promising strategy for specific treatment of numerous gene-associated human diseases by intentionally altering the gene expression in pathological cells. A successful clinical application of gene-based therapy depends on an efficient gene delivery system. Many efforts have been attempted to improve the safety and efficiency of gene-based therapies. Nanoparticles have been proved to be the most promising vehicles for clinical gene therapy due to their tunable size, shape, surface, and biological behaviors. In this review, the clinical development of nanoparticles for gene delivery will be particularly highlighted. Several promising candidates, which are closest to clinical applications, will be briefly reviewed. Then, the recent developments of nanoparticles for clinical gene therapy will be identified and summarized. Finally, the development of nanoparticles for clinical gene delivery in future will be prospected. © 2016 Official journal of the American Society of Gene & Cell Therapy


Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,CAS Changchun Institute of Applied Chemistry
Materials Research Bulletin | Year: 2017

The development of cost- and time-effective methods to synthesize graphene materials is very urgent in order to promote its large-scale application in electrochemical energy storage devices. Herein, graphene materials were synthesized by the electrochemical exfoliation (electrochemical oxidation) of graphite-clay rods with different clay:graphite ratios in aqueous solution and in short reaction time (1. h). The dual role of electrochemical oxidation reaction was presented: (1) the electrochemical oxidation reaction facilitates the exfoliation of pencil graphite leads and in-situ forms functional groups on graphene; (2) the electrochemical oxidation reaction enhances the Faradaic reaction in supercapacitor. The in-situ electrochemical oxidation and functionalization methods can transform low purity graphite to high-value graphene electrode materials for supercapacitors and lithium ion batteries. The specific capacitances of exfoliated graphene are 20-time larger than that of graphite-clay composites. This work provided a value-added way that can transform the low-purity graphite resources to high performance graphene electrode materials. © 2017 Elsevier Ltd.


Yan H.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook
PLoS ONE | Year: 2017

The basal ganglia neural circuit plays an important role in motor control. Despite the significant efforts, the understanding of the principles and underlying mechanisms of this modulatory circuit and the emergence of abnormal synchronized oscillations in movement disorders is still challenging. Dopamine loss has been proved to be responsible for Parkinson's disease. We quantitatively described the dynamics of the basal ganglia-thalamo-cortical circuit in Parkinson's disease in terms of the emergence of both abnormal firing rates and firing patterns in the circuit. We developed a potential landscape and flux framework for exploring the modulatory circuit. The driving force of the circuit can be decomposed into a gradient of the potential, which is associated with the steady-state probability distributions, and the curl probability flux term. We uncovered the underlying potential landscape as a Mexican hat-shape closed ring valley where abnormal oscillations emerge due to dopamine depletion. We quantified the global stability of the network through the topography of the landscape in terms of the barrier height, which is defined as the potential difference between the maximum potential inside the ring and the minimum potential along the ring. Both a higher barrier and a larger flux originated from detailed balance breaking result in more stable oscillations. Meanwhile, more energy is consumed to support the increasing flux. Global sensitivity analysis on the landscape topography and flux indicates how changes in underlying neural network regulatory wirings and external inputs influence the dynamics of the system. We validated two of the main hypotheses(direct inhibition hypothesis and output activation hypothesis) on the therapeutic mechanism of deep brain stimulation (DBS). We found GPe appears to be another effective stimulated target for DBS besides GPi and STN. Our approach provides a general way to quantitatively explore neural networks and may help for uncovering more efficacious therapies for movement disorders. © 2017 Yan, Wang.


Meng X.,CAS Changchun Institute of Applied Chemistry | Meng X.,Shandong University of Technology | Wang H.-N.,Shandong University of Technology | Song S.-Y.,CAS Changchun Institute of Applied Chemistry | Zhang H.-J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2017

Crystalline porous materials are currently a hot research topic in the field of proton-conducting materials. Crystalline porous materials include metal-organic frameworks (MOFs), coordination polymers (CPs), polyoxometalates (POMs) and covalent organic frameworks (COFs). The designable structures and high surface areas of these materials provide great opportunities to orderly accommodate proton carriers and to systemically modify the concentration and mobility of proton carriers in available spaces. Based on the understanding of the relationship between the structure and proton conductivity, controllable synthesis of porous materials with high proton conductivity will gradually be achieved. This review summarizes the emerging studies of these materials and their unique proton conductivities. © 2017 The Royal Society of Chemistry.


LI D.,CAS Changchun Institute of Applied Chemistry
Journal of Rare Earths | Year: 2017

This paper reviewed various systems such as neutral phosphorus and acid phosphorus, carboxylic acid and amine extractant for solvent extraction chemistry of yttrium, including thermodynamics, kinetics and yttrium extracting separation process containing the development course and new separation process. © 2017 The Chinese Society of Rare Earths


Huang C.,University of Akron | Chen Q.,CAS Changchun Institute of Applied Chemistry | Weiss R.A.,University of Akron
Macromolecules | Year: 2017

The linear viscoelastic (LVE) behavior of partially neutralized oligomeric sulfonated polystyrene (SPS) ionomers with different degrees of sulfonation (p) and degrees of neutralization (x) was investigated. The ionic dissociation time, τs, obtained from the reversible gelation model [Chen et al. Macromolecules 2015, 48, 1221-1230] is mainly controlled by the neutralization degree, x, rather than the functional group (i.e., sulfonic acid and metal sulfonate) concentration, p. For a fixed p, increasing x significantly increases τs and the zero shear viscosity, η0, especially near complete neutralization. These results explain the observations reported by Lundberg et al. [Ions in Polymers; American Chemical Society: 1980; Vol. 187, pp 67-76] that the increase of the viscosity of SPS ionomers with neutralization undergoes a substantial increase between 90% and 100% neutralization of the sulfonic acid groups to metal salts. This rapid increase of τs and η0 is probably related to the decrease of sulfonic acid groups in the ionic aggregates with increasing x. © 2016 American Chemical Society.


Zhang L.,CAS Changchun Institute of Applied Chemistry | Ding Z.C.,CAS Changchun Institute of Applied Chemistry | Tong T.,Jilin University | Liu J.,CAS Changchun Institute of Applied Chemistry
Nanoscale | Year: 2017

The graphene quantum dot (GQD) is a new kind of anode/cathode interlayer material for polymer solar cells (PSCs). The key requirement for a cathode interlayer (CIL) is a low work function. In this article, aiming at application as a CIL for PSCs, we report a general approach to tune the work function of GQD-modified electrodes using alkali metal cations, e.g. Li+, Na+, K+, Rb+ and Cs+. For ITO electrodes modified with these GQDs containing alkali metal cations, the work function can be finely tuned within the range of 4.0-4.5 eV. Owing to their low work function, GQDs containing K+, Rb+ and Cs+ can be used as CILs for PSCs. Their device performance is fairly comparable to that of the state-of-the-art CIL material ZnO. This work provides a rational approach to tune the properties of GQD and to design solution-processable electrode interlayer materials for organic electronic devices. © 2017 The Royal Society of Chemistry.


Tang P.,CAS Changchun Institute of Applied Chemistry | Tang P.,University of Chinese Academy of Sciences | Xiao D.,CAS Changchun Institute of Applied Chemistry | Wang B.,CAS Changchun Institute of Applied Chemistry
Chemical Communications | Year: 2017

A natural product inspired rapid access of 3-(aminomethyl)pyridine by one-pot reaction of 1-amidopyridin-1-ium salt with aminal followed by reductive cleavage of the N-N bond is developed. This C3-selective formal C-H activation of pyridine features a traceless umpolung of the 1-amidopyridin-1-ium salt toward a Mannich type C-C bond formation of the in situ generated 1-amido-2-dialkylamino-1,2-dihydropyridine intermediate. © The Royal Society of Chemistry.


Xue X.,Dalian University of Technology | Wang Y.,Dalian University of Technology | Han F.-S.,CAS Changchun Institute of Applied Chemistry
Chemical Communications | Year: 2017

The design and preparation of a chiral Pt nanocatalyst system possessing thermoregulated phase-separation property and its application in recyclable asymmetric hydrogenation of α-ketoesters are presented. © The Royal Society of Chemistry.


Luo J.,Institute of Materials Research and Engineering of Singapore | Xu M.,CAS Changchun Institute of Applied Chemistry | Li R.,CAS Changchun Institute of Applied Chemistry | Huang K.-W.,King Abdullah University of Science and Technology | And 8 more authors.
Journal of the American Chemical Society | Year: 2014

Porphyrin-based dyes recently have become good candidates for dye-sensitized solar cells (DSCs). However, the bottleneck is how to further improve their light-harvesting ability. In this work, N-annulated perylene (NP) was used to functionalize the Zn-porphyrin, and four "push-pull"-type NP-substituted and fused porphyrin dyes with intense absorption in the visible and even in the near-infrared (NIR) region were synthesized. Co(II/III)-based DSC device characterizations revealed that dyes WW-5 and WW-6, in which an ethynylene spacer is incorporated between the NP and porphyrin core, showed pantochromatic photon-to-current conversion efficiency action spectra in the visible and NIR region, with a further red-shift of about 90 and 60 nm, respectively, compared to the benchmark molecule YD2-o-C8. As a result, the short-circuit current density was largely increased, and the devices displayed power conversion efficiencies as high as 10.3% and 10.5%, respectively, which is comparable to that of the YD2-o-C8 cell (η = 10.5%) under the same conditions. On the other hand, the dye WW-3 in which the NP unit is directly attached to the porphyrin core showed a moderate power conversion efficiency (η = 5.6%) due to the inefficient π-conjugation, and the NP-fused dye WW-4 exhibited even poorer performance due to its low-lying LUMO energy level and nondisjointed HOMO/LUMO profile. Our detailed physical measurements (optical and electrochemical), density functional theory calculations, and photovoltaic characterizations disclosed that the energy level alignment, the molecular orbital profile, and dye aggregation all played very important roles on the interface electron transfer and charge recombination kinetics. © 2013 American Chemical Society.


Xue S.,CAS Changchun Institute of Applied Chemistry | Xue S.,University of Chinese Academy of Sciences | Zhao L.,CAS Changchun Institute of Applied Chemistry | Guo Y.-N.,CAS Changchun Institute of Applied Chemistry | And 3 more authors.
Chemical Communications | Year: 2012

A rare μ 4-OH centred square Dy 4 aggregate displays a field enhanced thermally activated mechanism with 3-fold increase in the single-molecule magnetic relaxation barrier upon application of an optimal field. © The Royal Society of Chemistry 2012.


Wang G.,CAS Changchun Institute of Applied Chemistry | Wang S.,Peking University | Cui Y.,CAS Changchun Institute of Applied Chemistry | Pan D.,CAS Changchun Institute of Applied Chemistry
Chemistry of Materials | Year: 2012

A novel and versatile metal-organic molecular precursor-based solution approach and the fabrication of high efficiency Cu(In,Ga)(S,Se) 2 solar cells are presented. Many types of metal oxides, hydroxides, and acetylacetonates (acac), such as Cu 2O, ZnO, SnO, Sb 2O 3, MnO, PbO, In(OH) 3, Cd(OH) 2, Ga(acac) 3, and so forth, can be easily dissolved in butyldithiocarbamic acid, forming thermally degradable metal-organic molecular precursor solutions. By developing a simple and green ethanol solution-processed route and tuning the chemical composition of the Cu(In,Ga)(S,Se) 2 thin film, as-fabricated solar cells exhibit an average power conversion efficiency up to 8.8%. © 2012 American Chemical Society.


Fu Q.,CAS Changchun Institute of Applied Chemistry | Fu Q.,University of Chinese Academy of Sciences | Chen J.,CAS Changchun Institute of Applied Chemistry | Zhang H.,Nanjing University of Posts and Telecommunications | And 2 more authors.
Optics Express | Year: 2013

By doping blue, green and red dyes into a bipolar host system, a simple single-EML white organic light-emitting diode (WOLED) with efficiency and color-stability trade-off was achieved by solution process. The resulting WOLED shows high efficiency (i.e., 36.5 cd/A and 15.7% at 1141 cd/m2), reduced efficiency roll-off (i.e., critical current density jc is as high as 140 mA/cm2) and, especially, extremely stable electroluminescence spectra with a slight CIE coordinate variation of (0.404 ± 0.004, 0.436 ± 0.001). The superior performance of the WOLED is attributed to the effective suppression of exciton quenching and charge trapping in the bipolar EML. © 2013 Optical Society of America.


Luo L.,Shanghai University | Zhu L.,Shanghai University | Zhu L.,CAS Changchun Institute of Applied Chemistry | Wang Z.,CAS Changchun Institute of Applied Chemistry
Bioelectrochemistry | Year: 2012

Here, we report a nonenzymatic amperometric glucose sensor based on copper oxide (CuO) nanocubes-graphene nanocomposite modified glassy carbon electrode (CuO-G-GCE). In this case, the graphene sheets were cast on the GCE directly. CuO nanocubes were obtained by oxidizing electrochemically deposited Cu on the graphene. The morphology of CuO-G nanocomposite was characterized by scanning electron microscopy. The CuO-G-GCE-based sensor exhibited excellent electrocatalytic activity and high stability for glucose oxidation. Under optimized conditions, the linearity between the current response and the glucose concentration was obtained in the range of 2μM to 4mM with a detection limit of 0.7μM (S/N=3), and a high sensitivity of 1360μAmM-1cm-2. The proposed electrode showed a fast response time (less than 5s) and a good reproducibility. The as-made sensor was applied to determine the glucose levels in clinic human serum samples with satisfactory results. In addition, the effects of common interfering species, including ascorbic acid, uric acid, dopamine and other carbohydrates, on the amperometric response of the sensor were investigated and discussed in detail. © 2012 Elsevier B.V.


Wu S.,Nanyang Technological University | Zeng Z.,Nanyang Technological University | He Q.,Nanyang Technological University | Wang Z.,Nanyang Technological University | And 6 more authors.
Small | Year: 2012

The electrochemical study of single-layer, 2D MoS2 nanosheets reveals a reduction peak in the cyclic voltammetry in NaCl aqueous solution. The electrochemically reduced MoS2 (rMoS2) shows good conductivity and fast electron transfer rate in the [Fe(CN)6] 3-/4- and [Ru(NH3)6]2+/3+ redox systems. The obtained rMoS2 can be used for glucose detection. In addition, it can selectively detect dopamine in the presence of ascorbic acid and uric acid. This novel material, rMoS2, is believed to be a good electrode material for electrochemical sensing applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jiao C.,National University of Singapore | Zu N.,CAS Changchun Institute of Applied Chemistry | Huang K.-W.,King Abdullah University of Science and Technology | Wang P.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Organic Letters | Year: 2011

Two perylene anhydride fused porphyrins 1 and 2 have been synthesized and employed successfully in dye-sensitized solar cells (DSCs). Both compounds showed broad incident monochromatic photon-to-current conversion efficiency spectra covering the entire visible spectral region and even extending into the near-infrared (NIR) region up to 1000 nm, which is impressive for ruthenium-free dyes in DSCs. © 2011 American Chemical Society.


Chen R.,Changchun Normal University | Liu Z.,CAS Changchun Institute of Applied Chemistry | Zhao J.,Changchun Normal University | Meng F.,Changchun Normal University | And 2 more authors.
Food Chemistry | Year: 2011

A water-soluble polysaccharide obtained from Acanthopanax senticosus leaves (ASL), was fractionated by DEAE-Sepharose fast-flow column chromatography, and purified by Sephadex G-75 gel-permeation column chromatography. The characteristics of ASP-2-1 were determined by chemical analysis, high-performance capillary electrophoresis (HPCE), high-performance gel-permeation chromatography (HPGPC). The results show that ASP-2-1 contained 89.47% carbohydrate, 7.45% uronic acid, 2.16% protein and seven kinds of monosaccharides including rhamnose, xylose, glucose, mannose, arabinose, galactose and glucuronic acid in a molar ratio of 7.45:18.63:25.15:0.93:8.35:2. 79:5.69, with an average molecular weight of about 14,573 Da. Furthermore, the immunobiological and antioxidant activities, in vitro, of ASP-2-1 were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and ferric-reducing antioxidant power assay (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH.), superoxide radical (.O2 -) and hydroxyl radical (.OH) free radical-scavenging assay, respectively. The results showed that ASP-2-1 exhibited significantly higher immunomodulatory activities against the lymphocyte proliferation in vitro, pronounced reductive power (FRAP value: 785.1 μM at 0.2 mg/ml), strong hydroxyl radical (89.56% at 1 mg/ml) scavenging activity, moderate superoxide radicals (65.32% at 1 mg/ml) and DPPH radicals (68.9% at 1 mg/ml) scavenging activities. ASP-2-1 should be explored as a novel and potential natural antioxidant and immunostimulating agent for use in functional foods or medicine. © 2011 Elsevier Ltd. All rights reserved.


Sheng L.,CAS Changchun Institute of Applied Chemistry | Sheng L.,Zhejiang Normal University | Ren J.,CAS Changchun Institute of Applied Chemistry | Miao Y.,Zhejiang Normal University | And 2 more authors.
Biosensors and Bioelectronics | Year: 2011

In this paper, we developed a simple method to detect fungi toxin (ochratoxin A) produced by Aspergillus Ochraceus and Penicillium verrucosumm, utilizing graphene oxide as quencher which can quench the fluorescence of FAM (carboxyfluorescein) attached to toxin-specific aptamer. By optimizing the experimental conditions, we obtained the detection limit of our sensing platform based on bare graphene oxide to be 1.9μM with a linear detection range from 2μM to 35μM. Selectivity of this sensing platform has been carefully investigated; the results showed that this sensor specifically responded to ochratoxin A without interference from other structure analogues (N-acetyl-. l-phenylalanine and warfarin) and with only limited interference from ochratoxin B. Experimental data showed that ochratoxin A as well as other structure analogues could adsorb onto the graphene oxide. As compared to the non-protected graphene oxide based biosensor, PVP-protected graphene oxide reveals much lower detection limit (21.8. nM) by two orders of magnitude under the optimized ratio of graphene oxide to PVP concentration. This sensor has also been challenged by testing 1% red wine containing buffer solution spiked with a series of concentration of ochratoxin A. © 2011 Elsevier B.V.


Guo Y.-N.,CAS Changchun Institute of Applied Chemistry | Guo Y.-N.,University of Chinese Academy of Sciences | Chen X.-H.,Fujian Normal University | Xue S.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Inorganic Chemistry | Year: 2012

Complexation of dysprosium(III) with the heterodonor chelating ligand o-vanillin picolinoylhydrazone (H 2ovph) in the presence of a carbonato ligand affords two novel Dy 6 and Dy 8 clusters, namely, [Dy 6(ovph) 4(Hpvph) 2Cl 4(H 2O) 2(CO 3) 2] ·CH 3OH·H 2O·CH 3CN (2) and [Dy 8(ovph) 8(CO 3) 4(H 2O) 8]·12CH 3CN·6H 2O (3). Compound 2 is composed of three petals of the Dy 2 units linked by two carbonato ligands, forming a triangular prism arrangement, while compound 3 possesses an octanuclear core with an unprecedented tub conformation, in which Dy(ovph) fragments are attached to the sides of the carbonato core. The static and dynamic magnetic properties are reported and discussed. In the Dy 6 aggregate, three Dy 2 "skeletons", having been well preserved (see the scheme), contribute to the single-molecule-magnet behavior with a relatively slow tunneling rate, while the Dy 8 cluster only exhibits a rather small relaxation barrier. © 2012 American Chemical Society.


Jin X.,Zhejiang Normal University | He B.,Zhejiang Normal University | Miao J.,Zhejiang Normal University | Yuan J.,Zhejiang Normal University | And 2 more authors.
Carbon | Year: 2012

PtRu and Pt nanoparticles were deposited on the surface of multiwalled carbon nanotubes (MWCNTs) with the assistance of phosphomolybdic acid (PMo) by a one-pot hydrothermal reduction strategy. Transmission electron microscopy shows a high-density PtRu (or Pt) nanoparticles uniformly dispersed on the surface of the MWCNTs with an average diameter of 1.8 nm for PtRu nanoparticles and 2.4 nm for Pt nanoparticles. Moreover, the as-prepared PMo/PtRu/MWCNT and PMo/Pt/MWCNT electrocatalysts are highly electroactive for the electrochemical oxidation of methanol. Cyclic voltammograms show a high electrochemical surface area (ESA) and a large current density for methanol oxidation at the modified electrode by PMo/PtRu/MWCNT and PMo/Pt/MWCNT electrocatalysts. Electrochemical impedance spectroscopy reveals a high CO tolerance for PMo/PtRu/MWCNT and PMo/Pt/MWCNT electrocatalysts in the electrochemical catalysis of methanol oxidation. For comparison, PtRu/MWCNT and Pt/MWCNT electrocatalysts were prepared in control experiments without PMo. The results demonstrate that PtRu and Pt nanoparticles deposited on MWCNTs in the presence of PMo were superior to those on MWCNTs without PMo in several respects including: (1) a smaller size and a higher dispersion; (2) a higher ESA; (3) a larger current density for methanol oxidation; (4) a higher tolerance for CO poisoning. © 2012 Elsevier Ltd. All rights reserved.


Zhu L.,Shanghai University | Zhu L.,CAS Changchun Institute of Applied Chemistry | Luo L.,Shanghai University | Wang Z.,CAS Changchun Institute of Applied Chemistry
Biosensors and Bioelectronics | Year: 2012

A novel protocol for development of DNA electrochemical biosensor based on thionine-graphene nanocomposite modified gold electrode was presented. The thionine-graphene nanocomposite layer with highly conductive property was characterized by scanning electron microscopy, transmission electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. An amino-substituted oligonucleotide probe was covalently grafted onto the surface of the thionine-graphene nanocomposite by the cross-linker glutaraldehyde. The hybridization reaction on the modified electrode was monitored by differential pulse voltammetry analysis using an electroactive intercalator daunomycin as the indicator. Under optimum conditions, the proposed biosensor exhibited high sensitivity and low detection limit for detecting complementary oligonucleotide. The complementary oligonucleotide could be quantified in a wide range of 1.0×10 -12 to 1.0×10 -7M with a good linearity (R 2=0.9976) and a low detection limit of 1.26×10 -13M (S/N=3). In addition, the biosensor was highly selective to discriminate one-base or two-base mismatched sequences. © 2012 Elsevier B.V.


Huang J.,Wuhan University | Sun N.,CAS Changchun Institute of Applied Chemistry | Dong Y.,Beijing Normal University | Tang R.,Wuhan University | And 6 more authors.
Advanced Functional Materials | Year: 2013

Four 4,4′-bis(1,2,2-triphenylvinyl)biphenyl (BTPE) derivatives, 4,4′-bis(1,2,2-triphenylvinyl)biphenyl, 2,3′-bis(1,2,2- triphenylvinyl)biphenyl, 2,4′-bis(1,2,2-triphenylvinyl)biphenyl, 3,3′-bis(1,2,2-triphenylvinyl)biphenyl and 3,4′-bis(1,2,2- triphenylvinyl)biphenyl (oTPE-mTPE, oTPE-pTPE, mTPE-mTPE, and mTPE-pTPE, respectively), are successfully synthesized and their thermal, optical, and electronic properties fully investigated. By merging two simple tetraphenylethene (TPE) units together through different linking positions, the π-conjugation length is effectively controlled to ensure the deep-blue emission. Because of the minor but intelligent structural modification, all the four fluorophores exhibit deep-blue emissions from 435 to 459 nm with Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of, respectively, (0.16, 0.14), (0.15, 0.11), (0.16, 0.14), and (0.16, 0.16), when fabricated as emitters in organic light-emitting diodes (OLEDs). This is completely different from BTPE with sky-blue emission (0.20, 0.36). Thus, these results may provide a novel and versatile approach for the design of deep-blue aggregation-induced emission (AIE) luminogens. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Guo Y.-N.,CAS Changchun Institute of Applied Chemistry | Guo Y.-N.,University of Chinese Academy of Sciences | Chen X.-H.,Fujian Normal University | Xue S.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Inorganic Chemistry | Year: 2011

Complexation of dysprosium(III) with the heterodonor chelating ligand o-vanillin picolinoylhydrazone (H2ovph) in the presence of different bases affords three new dinuclear dysprosium(III) coordination compounds, namely, [Dy2(ovph)2(NO3)2(H 2O)2]·2H2O (1), [Dy2(Hovph) (ovph)(NO3)2(H2O)4]·NO 3·2CH3OH·3H2O (2), and Na[Dy 2(Hovph)2(μ2-OH)(OH)(H2O) 5]·3Cl·3H2O (3), where the aroylhydrazone ligand adopts different coordination modes in respective structures depending on the reaction conditions, as revealed by single-crystal X-ray analyses to be due to their tautomeric maneuver. The magnetic properties of 1-3 are drastically distinct. Compounds 1 and 2 show single-molecule-magnet behavior, while no out-of-phase alternating-current signal is noticed for 3. The structural differences induced by the different coordinate fashions of the ligand may influence the strength of the local crystal field, the magnetic interactions between metal centers, and the local tensor of anisotropy on each Dy site and their relative orientations, therefore generating dissimilar dynamic magnetic behavior. © 2011 American Chemical Society.


Zhang G.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Xie Z.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University
Macromolecules | Year: 2011

A series of new isoindigo-based low banbap polymers, containing thiophene, thieno[3,2-b]thiophene and benzo[1,2-b:4,5-b′]dithiophene as donors, have been synthesized by Stille cross-coupling reaction. Their photophysical, electrochemical and photovoltaic properties have been investigated. These new polymers exhibit broad and strong absorption between 400 and 800 nm with absorption maxima around 700 nm. The HOMO energy levels of polymers vary between -5.20 and -5.49 eV and the LUMO energy levels range from -3.66 to -3.91 eV. The optical bandgaps of the polymers are optimized for solar cell applications and they are at about 1.5 eV. Polymer solar cells (PSC) based on these new polymers were fabricated with device structures of ITO/PEDOT:PSS/polymers: PC 71BM (1:2, w/w)/LiF/Al. The photovoltaic properties of the polymers have been evaluated under AM 1.5G illumination at 100 mW/cm2 with a solar simulator. The combination of broad absorption, optimal bandgap and well matched energy levels with those of PCBMs makes these isoindigo-based low bandbap polymers promising materials for photovoltaic applications. © 2011 American Chemical Society.


Qian G.,Carleton University | Abu H.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2011

A precursor strategy for the synthesis and screening of a series of conjugated donor-acceptor polymers is demonstrated by successful preparation of low band-gap polymers (P2-P5) containing triphenylamine as an electron donor and several heterocycles as acceptors, such as [1,2,5]thiadiazolo[3,4-g] quinoxaline, [1,2,5]thiadiazolo[3,4-i]dibenzo[a,c]phenazine, benzo[1,2-c:4,5-c′]bis([1,2,5]thiadiazole), and selenadiazole[3,4-f] benzo[c][1,2,5]thiadiazole, that are transformed from a single reactive polymer (P1). Polymers P2-P5 have the band gap of 1.71-1.29 eV and show the absorption and emission in the near infrared (NIR) spectral region. All the polymers are also NIR electrochromic. In particular, polymer P3 is electrochemically switchable between leaf-like green coloring and near-infrared absorbing states with an efficiency of 479 cm2 C-1 at 1310 nm or 232 cm2 C-1 at 1550 nm, making it potentially useful for electrically switchable day-to-night camouflage applications. © 2011 The Royal Society of Chemistry.


Ghosh K.R.,Carleton University | Saha S.K.,Carleton University | Gao J.P.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Chemical Communications | Year: 2014

A fluorescence sensory polymer containing the pentiptycene and tetraphenylethylene units linked by acetylene was synthesized for direct detection of isocyanates in air. Eight industrially available aliphatic and aromatic isocyanates were tested. The polymer film shows a rapid fluorescence quenching response to any type of isocyanates with a ppt level of detection limit, which is much lower than the permissible exposure limit of 5 ppb. © 2014 The Royal Society of Chemistry.


Zhang G.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Xie Z.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University
Solar Energy Materials and Solar Cells | Year: 2011

A new 3,6-dithien-2-yl-2,5-dialkylpyrrolo[3,4-c]pyrrole-1,4-dione (DTDPP) based polymer, poly{thieno[3,2-b]thiophene-alt-3,6-dithien-2-yl-2,5-di(2- octyldodecyl)-pyrrolo[3,4-c]pyrrole-1,4-dione} (PTT-DTDPP) was synthesized by the Stille coupling reaction. The polymer shows a broad absorption in visible and near infrared region and displays suitable HOMO/LUMO energy levels for marching with those of PCBM acceptor. The photovoltaic properties of the polymer were studied by bulk heterojunction solar cell devices using PTT-DTDPP as donor and PC71BM as acceptor. The power conversion efficiency of device achieved 1.60% under the illumination of AM1.5 G, 100 mW/cm2. © 2011 Elsevier B.V. All rights reserved.


Shang L.,Karlsruhe Institute of Technology | Dong S.,CAS Changchun Institute of Applied Chemistry | Nienhaus G.U.,Karlsruhe Institute of Technology | Nienhaus G.U.,University of Illinois at Urbana - Champaign
Nano Today | Year: 2011

Recent advances in nanotechnology have given rise to a new class of fluorescent labels, fluorescent metal nanoclusters, e.g., Au and Ag. These nanoclusters are of significant interest because they provide the missing link between atomic and nanoparticle behavior in metals. Composed of a few to a hundred atoms, their sizes are comparable to the Fermi wavelength of electrons, resulting in molecule-like properties including discrete electronic states and size-dependent fluorescence. Fluorescent metal nanoclusters have an attractive set of features, such as ultrasmall size, good biocompatibility and excellent photostability, making them ideal fluorescent labels for biological applications. In this review, we summarize synthesis strategies of water-soluble fluorescent metal nanoclusters and their optical properties, highlight recent advances in their application for ultrasensitive biological detection and fluorescent biological imaging, and finally discuss current challenges for their potential biomedical applications. © 2011 Elsevier Ltd. All rights reserved.


Ma P.,CAS Changchun Institute of Applied Chemistry | Xiao H.,University of Notre Dame | Li X.,Northeast Normal University | Li C.,CAS Changchun Institute of Applied Chemistry | And 5 more authors.
Advanced Materials | Year: 2013

By combining upconversion nanoparticles with the cisplatin (IV) prodrug we have demonstrated that a stable and multifunctional drug delivery system can be designed that will both reduce the drawbacks of cisplatin and give insight in to its in vitro/in vivo imaging. The up/down-conversion fluorescence are detectable and show obvious co-localization, demonstrating that the nanoparticles are rather stable inside cells and retain the UCNPs and block copolymer. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Du X.,CAS Changchun Institute of Applied Chemistry | Du X.,University of Chinese Academy of Sciences | Qi J.,CAS Changchun Institute of Applied Chemistry | Qi J.,University of Chinese Academy of Sciences | And 4 more authors.
Chemistry of Materials | Year: 2012

A family of donor-acceptor-donor (D-A-D) type near-infrared (NIR) fluorophores containing rigid nonplanar conjugated tetraphenylethene (TPE) moieties was designed and synthesized through Stille coupling reactions with electron-deficient [1,2,5]thiadiazolo[3,4-g]quinoxaline (QTD) or benzo[1,2-c;4,5-c′]bis[1,2,5]thiadiazole (BBTD) as acceptors. The absorption, fluorescence, and electrochemical properties were studied. These compounds exhibited good aggregation-induced emission enhancement (AIEE) property, as a result of the twisted TPE units, which restrict the intramolecular rotation and reduce the π-π stacking. Photoluminescence of these chromophores ranges from 600 to 1100 nm, and their HOMO-LUMO gaps are between 1.85 and 1.50 eV. Non-doped organic light-emitting diodes (OLEDs) based on these fluorophores were made and exhibited EL emission spectra peaking from 706 to 864 nm. The external quantum efficiency (EQE) of these devices ranged from 0.89% to 0.20% and remained fairly constant over a range of current density of 100-300 mA cm -2. The device with the highest solid fluorescence efficiency emitter 1a shows the best performance with a maximum radiance of 2917 mW Sr -1 m -2 and EQE of 0.89%. A contrast between nondoped and doped OLEDs with these materials confirms that AIEE compounds are suitable for fabricate efficient nondoped NIR OLEDs. © 2012 American Chemical Society.


Qian G.,Carleton University | Qi J.,CAS Changchun Institute of Applied Chemistry | Qi J.,University of Chinese Academy of Sciences | Davey J.A.,Carleton University | And 3 more authors.
Chemistry of Materials | Year: 2012

A family of pyrrolo[3,4-c]pyrrol-1(2H)-one (PPO) and 2,5-diazapentalene (DAP) chromophores and DAP-containing polymers were synthesized, and their optical and electrochemical properties were studied. PPO and DAP chromophores are readily obtained by chemical transformation of the lactam unit in diketopyrrolopyrrole (DPP) dyes and can be used as versatile building blocks for construction of a variety of conjugated low-band-gap compounds and polymers. In comparison with the DPP chromophores, PPO and DAP chromophores have narrower energy gaps and low-lying HOMO levels in the order DPP > PPO > DAP. Interestingly, the PPO and DAP chromophores exhibit unique visible and near-infrared halochromic and halofluoric properties. The emission spectrum of DAP-containing polymer 6d covers the telecommunication window including the wavelength of 1310 nm. The photodetector with a device configuration of ITO/PEDOT:PSS (35 nm)/active layer (100 nm)/Al (100 nm) was fabricated using a blend of polymer 6d and [6,6]-phenyl-C 61-butyric acid methyl ester (PC 61BM) in a weight ratio of 1:3 as the active layer and exhibited photocurrent spectral response from 400 to 1000 nm and the detectivity in an order of 10 11 Jones at 800 nm. © 2012 American Chemical Society.


Liu Y.,CAS Changchun Institute of Applied Chemistry | Ai K.,CAS Changchun Institute of Applied Chemistry | Cheng X.,Heilongjiang University | Huo L.,Heilongjiang University | Lu L.,CAS Changchun Institute of Applied Chemistry
Advanced Functional Materials | Year: 2010

A novel, gold-nanocluster-based fluorescent sensor for cyanide in aqueous solution, which is based on the cyanide etching-induced fluorescence quenching of gold nanoclusters, is reported. In addition to offering high selectivity due to the unique Eisner reaction between cyanide and the gold atoms of gold nanoclusters, this facile, environmentally friendly and costeffective method provides high sensitivity. With this sensor, the lowest concentration to quantify cyanide ions could be down to 200 X 10-9 M, which is approximately 14 times lower than the maximum level (2.7 X 10-6M) of cyanide in drinking water permitted by the World Health Organization (WHO). Furthermore, several real water samples spiked with cyanide, including local groundwater, tap water, pond water, and lake water, are analyzed using the sensing system, and experimental results show that this fluorescent sensor exhibits excellent recoveries (over 93%). This gold-nanocluster-based fluorescent sensor could find applications in highly sensitive and selective detection of cyanide in food, soil, water, and biological samples. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.


Liu Y.,CAS Changchun Institute of Applied Chemistry | Wolfrum B.,Jülich Research Center | Huske M.,Jülich Research Center | Offenhausser A.,Jülich Research Center | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

Golden transistor: A chip-based molecular transistor concept is based on an electrochemical rectifier. The device can perform transistor-like functions with opposite current directions depending on the redox inputs. The unidirectional current recorded at a chemically modified collector electrode can be tuned by the potential applied to an independent generator electrode, which allows switching of the output current and information encoding. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yu D.,Heilongjiang University | Zhao F.,CAS Changchun Institute of Applied Chemistry | Han C.,Heilongjiang University | Xu H.,Heilongjiang University | And 5 more authors.
Advanced Materials | Year: 2012

The effective strategy of indirect linakge for constructing ternary ambipolar phosphine oxide (PO) hosts with the high first triplet energy levels (T 1) was successfully demonstrated. The interplay between the chromophore, hole and electron transporting moieties was effectively restrained. Both of T 1 as high as 3.0 eV and ambipolar characteristics were perfectly realized, which consequently resulted in the highly efficient blue-emitting phosphorescent organic light-emitting diodes with low driving voltage and stable efficiencies. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Qian G.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Advanced Materials | Year: 2012

A series of 2,5-diazapentalene containing dyes with tunable energy gaps are visible and near-infrared halochromic towards various acids and their protonated counterparts represent a new class of thermochromic materials with the near-infrared absorption being switched on at room temperature and off above 50 °C. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang G.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Xie Z.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University
Polymer | Year: 2011

New donor/acceptor polymers PBDTTPT1 and PBDTTPT2 with alternating benzodithiophene (BDT) and bisthiophene-dioxopyrrolothiophene (TPT) units were synthesized by Stille coupling reaction. The polymers had optical bandgaps of 1.78 and 1.82 eV, and HOMO energy levels of -5.30 and -5.35 eV for PBDTTPT1 and PBDTTPT2, respectively. Polymeric solar cell devices based on these copolymers as donors and PC71BM as acceptor showed the highest open circuit voltage of 0.95 V and power conversion efficiency of 2.68% under the illumination of AM 1.5, 100 mW/cm2. © 2010 Elsevier Ltd. All rights reserved.


Wei G.,University of Bremen | Zhang Y.,CAS Changchun Institute of Applied Chemistry | Steckbeck S.,University of Bremen | Su Z.,Beijing University of Chemical Technology | Li Z.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

Biomimetic synthesis is one of the facile strategies for creating novel nanostructured materials. Here we reported ferritin (Fr)-mediated biomimetic synthesis of FePt nanoparticles (NPs) on graphene nanosheets (GNs). GNs were noncovalently modified with 1-pyrenebutyric acid N-hydroxysuccinimide ester to provide binding sites for Fr molecules. The successful modification was demonstrated by X-ray photoelectron spectroscopy (XPS) and the formation of GN-Fr nanohybrids were identified with atomic force microscopy (AFM) and transmission electron microscopy (TEM). FePt NPs were synthesized by chemical reduction of metallic Fe 2+ and PtCl 6 2- that entered the core of Frs. The created GN-FePt nanohybrids exhibit multifunctions like high water-solubility, ferromagnetism, fluorescence, and enhanced electrocatalytic activity. The synthesized GN-FePt nanohybrids have potential applications in drug delivery, cell imaging, and biosensors. © The Royal Society of Chemistry 2012.


Yang J.,Central South University | Yan D.,CAS Changchun Institute of Applied Chemistry | Jones T.S.,University of Warwick
Chemical Reviews | Year: 2015

Molecular template growth (MTG) is a newly developed method for fabricating high-quality organic semiconductor thin films with controllable morphologies, molecular orientations, electronic structures, and interface properties to produce high-performance organic electronic and optoelectronic devices. There are several MTG methods with different molecular template materials and growth behaviors, including multiphenyl- and multithiophene-based MTG, and perylene-derivative MTG. Extensive research works have also revealed that Individualized methods for fabricating high-quality organic semiconductor thin films with controllable thin-film properties can be developed on the basis of specific understandings of the growth behaviors of organic semiconductor molecules and the desired device structures.


Yang W.,CAS Changchun Institute of Applied Chemistry | Tian T.,CAS Changchun Institute of Applied Chemistry | Wu H.-Y.,CAS Changchun Institute of Applied Chemistry | Pan Q.-J.,Heilongjiang University | And 2 more authors.
Inorganic Chemistry | Year: 2013

Six uranyl phosphonates and sulfonates have been hydrothermally synthesized, namely, (H2tib)[(UO2)3(PO 3C6H5)4]·2H2O (UPhP-1), Zn(pi)2(UO2)(PO3C6H 5)2 (UPhP-2), Zn(dib)(UO2)(PO3C 6H5)2·2H2O (UPhP-3), (HTEA)[(UO2)(5-SP)] (USP-1), (Hdib)2[(UO2) 2(OH)(O)(5-SP)] (USP-2), and Zn(phen)3(UO 2)2(3-SP)2 (USP-3) (tib = 1,3,5-tri(1H- imidazol-1-yl)benzene, pi = 1-phenyl-1H-imidazole, dib = 1,4-di(1H-imidazol-1- yl)benzene, TEA = triethylamine, phen = 1,10-phenanthroline, 5-SP = 5-sulfoisophthalic acid, and 3-SP = 3-sulfoisophthalic acid). UPhP-1 has been determined to be a layered structure constructed by UO7 pentagonal bipyramids, UO6 octahedra, and phenylphosphonates. Protonated tib plays a role in balancing the negative charge and holding its structure together. UPhP-2 is made up of UO6 octahedra, ZnO2N 2 tetrahedra and PO3C tetrahedra in phenylphosphonates, forming a 1D assembly, which is stabilized by chelate phen ligand. Further connection of such chainlike structure via dib yields a 2D layered architecture of UPhP-3. Although sulfonate group possesses similar tetrahedral structure as the phosphonate group, a unidentated coordination mode is only found in this work. UO7 pentagonal bipyramids are linked by 5-SP to form the layered assembly of USP-1. USP-2 also consists of the same sulfonate ligand, but features tetranulear uranyl clusters. Similarly, protonated TEA and dib molecules enable stabilization of their structures, respectively. Formed by dinuclear uranyl cluster and 3-SP ligand, USP-3 appears as a 1D arrangement, in which Zn(phen)3 acts as the counterion to compensate the negative charge. All of these compounds have been characterized by IR and photoluminescent spectroscopy. Their characteristic emissions have been attributed as transition properties of uranyl cations. © 2013 American Chemical Society.


Wu D.,Nankai University | Wu D.,Institute of Seawater Desalination And Multipurpose Utilization | Song X.,Nankai University | Tang T.,CAS Changchun Institute of Applied Chemistry | Zhao H.,Nankai University
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2010

Well-defined macromolecular brushes with poly (N-isopropyl acrylamide) (PNIPAM) side chains on random copolymer backbones were synthesized by "grafting from" approach based on click chemistry and reversible additionfragmentation chain transfer (RAFT) polymerization. To prepare macromolecular brushes, two linear random copolymers of 2-(trimethylsilyloxy) ethyl methacrylate (HEMA-TMS) and methyl methacrylate (MMA) (poly(MMA-co-HEMA- TMS)) were synthesized by atom transfer radical polymerization and were subsequently derivated to azide-containing polymers. Novel alkyne-terminated RAFT chain transfer agent (CTA) was grafted to polymer backbones by copper-catalyzed 1,3-dipolar cycloaddition (azide-alkyne click chemistry), and macro-RAFT CTAs were obtained. PNIPAM side chains were prepared by RAFT polymerization. The macromolecular brushes have well-defined structures, controlled molecular weights, and molecular weight distributions (M w/Mn ≦ 1.23). The RAFT polymerization of NIPAM exhibited pseudo-first-order kinetics and a linear molecular weight dependence on monomer conversion, and no detectable termination was observed in the polymerization. The macromolecular brushes can self-assemble into micelles in aqueous solution. © 2009 Wiley Periodicals, Inc.


Zhang G.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University | Xie Z.,CAS Changchun Institute of Applied Chemistry
Polymer | Year: 2010

Three new low bandgap conjugated copolymers with 3,4-ethylenedioxythiophene (EDOT) as donor and 2,3-bis(4-octyloxyphenyl)-quinoxaline (P1), 2,3-bis(4-octyloxyphenyl)-thiadiazol-quinoxaline (P2, P3) as acceptors were synthesized by Stille cross-coupling reaction, and their optical and electrochemical properties were studied. These polymers exhibited optical bandgap of 1.77, 1.29 and 1.13 eV, for P1, P2 and P3, respectively. Photovoltaic cells with device configuration of ITO/PEDOT: PSS/Copolymer: PCBM (1:4 w/w)/LiF/Al were fabricated. The measurements revealed an open-circuit voltage (Voc) of 0.52 V, short-circuit current density (Jsc) of 3.24 mA/cm2 and power conversion efficiency (PCE) of 0.60% for P1, and showed a Voc of 0.33 V, Jsc of 2.11 mA/cm2, PCE of 0.39% for P2. © 2010 Elsevier Ltd.


Zhang G.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University | Xie Z.,CAS Changchun Institute of Applied Chemistry
Chemical Communications | Year: 2010

New donor/acceptor polymers PBDTDPT1 and PBDTDPT2 with alternating benzodithiophene and N-alkylated dioxopyrrolo-thiophene were synthesized. The new polymers had deep HOMO levels of -5.42 and -5.44 eV for PBDTDPT1 and PBDTDPT2, respectively. A PBDTDPT2 based BHJ solar cell device achieved a PCE of 4.79% and Voc of 0.91 V. © 2010 The Royal Society of Chemistry.


Hao W.,Carleton University | McBride A.,Carleton University | McBride S.,Carleton University | Gao J.P.,Carleton University | And 2 more authors.
Journal of Materials Chemistry | Year: 2011

A highly efficient colorimetric and fluorescence turn-on molecular probe for sensitive and selective detection of biologically important cysteine (Cys) in human plasma is demonstrated using a new zwitterionic dye (M1). The sensing mechanism involves release of the blue-colored and fluorescent M1 from its non-fluorescent, pale-yellow copper complex (M1-Cu) upon exposure to Cys. The new dye has the desired properties suitable for bio-sensing applications, such as distinct blue color, near-infrared (NIR) fluorescence at the wavelength of 875 nm, a large Stokes shift (195 nm), high solubility and stability. This new probe shows both colorimetric and fluorescent responses specifically to Cys over other naturally occurring amino acids, amines and some bioactive thiols and allows for detection of Cys in aqueous solution with a low detection limit of 4.07 × 10-6 M and in human plasma at the physiologically relevant levels. © 2011 The Royal Society of Chemistry.


Wei H.,CAS Changchun Institute of Applied Chemistry | Wei H.,University of Illinois at Urbana - Champaign | Wang E.,CAS Changchun Institute of Applied Chemistry
Luminescence | Year: 2011

Electrochemiluminescence (ECL) of tris(2,2′-bipyridyl)ruthenium(II) [Ru(bpy)3 2+] is an active research area and includes the synthesis of ECL-active materials, mechanistic studies and broad applications. Extensive research has been focused on this area, due to its scientific and practical importance. In this mini-review we focus on the bio-related applications of ECL. After a brief introduction to Ru(bpy)3 2+ ECL and its mechanisms, its application in constructing an effective bioassay is discussed in detail. Three types of ECL assay are covered: DNA, immunoassay and functional nucleic acid sensors. Finally, future directions for these assays are discussed. Copyright © 2011 John Wiley & Sons, Ltd.


Ai K.,CAS Changchun Institute of Applied Chemistry | Liu Y.,CAS Changchun Institute of Applied Chemistry | Liu Y.,University of Chinese Academy of Sciences | Lu L.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of Materials Chemistry | Year: 2011

A facile and efficient strategy is described for the fabrication of soluble reduced graphene oxide (rGO) sheets. Different from the conventional strategies, the proposed method is based on the reduction of graphene oxide by an endogenous reducing agent from a most widely used and cost-effective solvent, without adding any other toxic reducing agent. Simultaneously, this solvent can serve as an effective stabilizer, avoiding complicated and time-consuming modification procedures. The as-prepared rGO sheets not only exhibit high reduction level and conductivity, but also can be well dispersed in many solvents. Of particular significance is that rGO sheets can be produced in large quantities. These advantages endow this proposed synthetic approach great potential applications in the construction of high-performance graphene-based devices at low cost, as demonstrated in our study of NO gas sensing. © 2011 The Royal Society of Chemistry.


Zhang L.,CAS Changchun Institute of Applied Chemistry | Zhang L.,University of Chinese Academy of Sciences | Niu W.,CAS Changchun Institute of Applied Chemistry | Niu W.,University of Chinese Academy of Sciences | And 2 more authors.
Chemical Communications | Year: 2011

Concave trisoctahedral (TOH) Pd@Au core-shell nanocrystals bound by {331} facets have been synthesized for the first time. Pd nanocubes and cetyltrimethylammonium chloride were used as the structure-directing cores and capping agents, respectively. Their optical and electrocatalytic properties were investigated. © 2011 The Royal Society of Chemistry.


Ghosh K.R.,Carleton University | Saha S.K.,Carleton University | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Polymer Chemistry | Year: 2014

A fluorescence sensory polymer (P1) consisting of pentiptycene and tetraphenylethene (TPE) units linked by acetylene was synthesized for direct detection of explosives in solution and air. At the same time, the effectiveness of thicker film in the presence of the TPE moiety for the detection of explosives was investigated. Fluorescence turn-off detection of picric acid (PA) was carried out in H2O-THF mixture containing 90% water, where the TPE units of the polymer are in a highly emissive aggregation state. Polymer P1 exhibits a fluorescence quenching response of 24% with addition of 4.36 × 10-8 M PA and 98% with the PA concentration at 4.7 × 10 -6 M. For a thinner film (4 nm) of P1 after exposure to dinitrotoluene for 10 s, the fluorescence intensity dropped 48% and it continued to drop 97% after 300 s, the corresponding values being 29% and 72% for thicker film (75 nm), respectively. These results indicate that P1 is a promising material for direct detection of nitro explosives in air and solution at ppb levels, and the TPE moiety inside the polymer improves the sensitivity and effectiveness of thicker films. © 2014 the Partner Organisations.


Hu C.,Shanghai JiaoTong University | Fu Y.,CAS Changchun Institute of Applied Chemistry | Li S.,Shanghai JiaoTong University | Xie Z.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,Shanghai JiaoTong University
Polymer Chemistry | Year: 2012

Donor-acceptor conjugated polymers based on benzo[1,2-b:5,4-b′] difuran (syn-BDF) or benzo[1,2-b:5,4-b′]difuran (anti-BDF) as donors and isoindigo as acceptors were synthesized by Stille cross-coupling reaction. The effects of syn- and anti-repeating units on optical, electrochemical and photovoltaic properties of polymers were investigated. The anti-PBDFID displayed lower optical bandgap and higher HOMO energy level than syn-PBDFID. The syn-PBDFID had better solubility than anti-PBDFID. The energy levels of two new polymers were compared with some related benzo[1,2-b:4,5-b′]dithiophenes (BDTs) based polymers. The results suggested that the utilization of less conjugated repeating units such as syn-BDF and the elimination of electron donating groups on the central phenyl ring of BDF can effectively lower the HOMO energy level of polymer. The low HOMO energy level of syn-PBDFID enabled high open circuit voltages in PSC devices. This journal is © 2012 The Royal Society of Chemistry.


Yang W.,CAS Changchun Institute of Applied Chemistry | Wu H.-Y.,CAS Changchun Institute of Applied Chemistry | Wang R.-X.,CAS Changchun Institute of Applied Chemistry | Pan Q.-J.,Heilongjiang University | And 2 more authors.
Inorganic Chemistry | Year: 2012

In this work, we demonstrate a family of new inorganic-organic hybrid uranyl diphosphonates based on 1-hydroxyethylidenediphosphonic acid (H 4L) linker by using hydrothermal method. These compounds, (Hbpi)[(UO 2)(H 2O)(HL)]·H 2O (UP-1), represents 1D structure, (Hbpi)[(UO 2)(H 2O)(HL)] (UP-2), (H 2dib) 0.5[(UO 2)(H 2O)(HL)] (UP-3), and [(UO 2)(H 2O)(H 2L)]·2H 2O (UP-4) feature 2D architectures, (H 2bipy){[(UO 2)(H 2O)] 2[(UO 2)(H 2O) 2](L) 2}·2H 2O (UP-5), and (H 3O) 2{[(UO 2)(H 2O)] 3(L) 2}·2H 2O (UP-6) adopt 3D networks (bpi: 1-(biphenyl-4-yl)-1H-imidazole, dib: 1,4-di(1H-imidazol-1-yl)benzene, bipy: 2,2′-bipyridine). Among them, UP-1, UP-2, UP-3, and UP-4 possess the same structural building unit but with different structures. UP-5 and UP-6 feature the same UO 2/L ratio of 3:2 but a different structural building unit. Photoluminescence studies reveal that UP-5 displays characteristic emissions of uranyl cations. Ion-exchange experiments demonstrate that the H 3O + in UP-6 can be easily and selectively exchanged by monovalent cations including Na +, K +, Cs +, and Ag + cations, whereas the framework retains identical as confirmed by single-crystal X-ray diffractions. © 2012 American Chemical Society.


Tian T.,CAS Changchun Institute of Applied Chemistry | Yang W.,CAS Changchun Institute of Applied Chemistry | Pan Q.-J.,Heilongjiang University | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry
Inorganic Chemistry | Year: 2012

Two new uranyl arsonates, Zn(UO 2)(PhAsO 3) 2L·H 2O [L = 1,10-phenanthroline (1) and 2,2-bipyridine (2)], have been synthesized by hydrothermal reactions of phenylarsonic acid, L, and ZnUO 2(OAc) 4·7H 2O. Single-crystal X-ray analyses demonstrate that these two compounds are isostructural and exhibit one-dimensional chains in which U VI and Zn II cations are directly connected by the yl oxygen atoms and additionally bridged by arsonate groups. Both compounds represent the first examples of uranyl arsonates with heterometallic cation-cation interactions. © 2012 American Chemical Society.


Yuan B.,CAS Changchun Institute of Applied Chemistry | Zheng C.,Heilongjiang University | Teng H.,Jilin University | You T.,CAS Changchun Institute of Applied Chemistry
Journal of Chromatography A | Year: 2010

A rapid and simple method was demonstrated for the analysis of atropine, anisodamine, and scopolamine by nonaqueous capillary electrophoresis (NACE) coupled with electrochemiluminescence (ECL) and electrochemistry (EC) dual detection. The mixture of acetonitrile (ACN) and 2-propanol containing 1 M acetic acid (HAc), 20 mM sodium acetate (NaAc), and 2.5 mM tetrabutylammonium perchlorate (TBAP) was used as the electrophoretic buffer. Although a short capillary of 18 cm was used, the decoupler was not needed and the separation efficiency was good. The linear ranges of atropine, anisodamine, and scopolamine were 0.5-50, 5-2000, and 50-2000 μM, respectively. For six replicate measurements of 100 μM scopolamine, 15 μM atropine, and 200 μM anisodamine, the RSDs of ECL intensity, EC current, and migration time were less than 3.6%, 4.5%, and 0.3%, respectively. In addition, because the organic buffer was used, the working electrode (Pt) was not easily fouled and did not need reactivation. The method was also applied for the determination of these three alkaloids in Flos daturae extract. © 2009 Elsevier B.V. All rights reserved.


Qian G.,Carleton University | Qi J.,CAS Changchun Institute of Applied Chemistry | Qi J.,University of Chinese Academy of Sciences | Wang Z.Y.,Carleton University | Wang Z.Y.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

The two pairs of structurally related donor-acceptor polymers (P1-P4) derived from diketopyrrolopyrrole (DPP) and diazapentalene (DAP) building blocks were synthesized and compared for their optical and photovoltaic properties with potential applications in solar cells and near-infrared (NIR) photodetectors. Having the electron-rich fluorene and bis(2′-thienyl) pyrrole (TPT) units as donors, the synthesized donor-acceptor polymers have band gap levels in the range 1.22-1.79 eV. The solar cells based on the blend of P2 (DPP-TPT polymer) and PC 71BM exhibited the best performance, showing a V oc of 0.61 V, J sc of 10.38 mA cm -2, FF of 0.44 and PCE of 2.8%. The photodetector based on the NIR-absorbing P4 (DAP-TPT polymer) displayed a good photovoltaic response over a wide spectral range of 400-1100 nm and an EQE of 13% and detectivity of 2.3 × 10 10 Jones at 800 nm. © 2012 The Royal Society of Chemistry.


Dai Y.,CAS Changchun Institute of Applied Chemistry | Dai Y.,University of Chinese Academy of Sciences | Xiao H.,University of Notre Dame | Liu J.,Jilin University | And 8 more authors.
Journal of the American Chemical Society | Year: 2013

Controlling anticancer drug activity and release on demand is very significant in cancer therapy. The photoactivated platinum(IV) pro-drug is stable in the dark and can be activated by UV light. In this study, we develop a multifunctional drug delivery system combining upconversion luminescence/magnetic resonance/computer tomography trimodality imaging and NIR-activated platinum pro-drug delivery. We use the core-shell structured upconversion nanoparticles to convert the absorbed NIR light into UV to activate the trans-platinum(IV) pro-drug, trans,trans,trans-[Pt(N3) 2(NH3)(py)(O2CCH2CH 2COOH)2]. Compared with using the UV directly, the NIR has a higher tissue penetration depth and is less harmful to health. Meanwhile, the upconversion nanoparticles can effectively deliver the platinum(IV) pro-drugs into the cells by endocytosis. The mice treated with pro-drug-conjugated nanoparticles under near-infrared (NIR) irradiation demonstrated better inhibition of tumor growth than that under direct UV irradiation. This multifunctional nanocomposite could be used as multimodality bioimaging contrast agents and transducers by converting NIR light into UV for control of drug activity in practical cancer therapy. © 2013 American Chemical Society.


Wang T.,CAS Changchun Institute of Applied Chemistry | Wang T.,University of Chinese Academy of Sciences | Bai J.,CAS Changchun Institute of Applied Chemistry | Jiang X.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
ACS Nano | Year: 2012

It is well-known that nanomaterials are capable of entering living cells, often by utilizing the cells' endocytic mechanisms. Passive penetration of the lipid bilayer may, however, occur as an alternative process. Here we have focused on the passive transport of small nanoparticles across the plasma membranes of red blood cells, which are incapable of endocytosis. By using fluorescence microscopy, we have observed that zwitterionic quantum dots penetrate through the cell membranes so that they can be found inside the cells. The penetration-induced structural changes of the lipid bilayer were explored by surface-enhanced infrared absorption spectroscopy and electrochemistry studies of model membranes prepared on solid supports with lipid compositions identical to those of red blood cell membranes. A detailed analysis of the infrared spectra revealed a markedly enhanced flexibility of the lipid bilayers in the presence of nanoparticles. The electrochemistry data showed that the overall membrane structure remained intact; however, no persistent holes were formed in the bilayers. © 2012 American Chemical Society.


Lu M.F.,CAS Changchun Institute of Applied Chemistry | Waerenborgh J.C.,University of Lisbon | Greaves C.,University of Birmingham
Angewandte Chemie - International Edition | Year: 2013

Mix and match: Topotactic hydride reduction allows the first synthesis of the fully reduced parent phase, Sr4Fe6O12, of the important family Sr4Fe6O13±δ. The structure provides a rare example of pairs of edge-linked tetrahedra, in this case containing a random arrangement of FeII and Fe III centers at 300 K. On cooling, charge order occurs so that each pair of tetrahedra has one FeII (white) and one FeIII (black) center. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lin S.-Y.,CAS Changchun Institute of Applied Chemistry | Lin S.-Y.,University of Chinese Academy of Sciences | Wernsdorfer W.,CNRS Neel Institute | Ungur L.,Catholic University of Leuven | And 6 more authors.
Angewandte Chemie - International Edition | Year: 2012

A hexanuclear dysprosium(III) compound constructed by two Dy3 triangles in an edge-to-edge arrangement perfectly retains a nonmagnetic ground state and single-molecular-magnet behavior. Such an arrangement and the strong couplings over a μ4-O2- ion stabilize a similar arrangement of toroidal moments in the ground state, thus maximizing the toroidal moment of the complex. (Picture: Dy purple, C gray, N blue, O red.) Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Shao S.,Linköping University | Liu J.,CAS Changchun Institute of Applied Chemistry | Bergqvist J.,Linköping University | Shi S.,Linköping University | And 4 more authors.
Advanced Energy Materials | Year: 2013

A solution-processed neutral hole transport layer is developed by in situ formation of MoO3 in aqueous PEDOT:PSS dispersion (MoO3 -PEDOT:PSS). This MoO3 -PEDOT:PSS composite fi lm takes advantage of both the highly conductive PEDOT:PSS and the ambient conditions stability of MoO3 ; consequently it possesses a smooth surface and considerably reduced hygroscopicity. The resulting bulk heterojunction polymer solar cells (BHJ PSC) based on poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt- thiophene- 2,5-diyl] (TQ1):[6,6]-phenyl-C 71 -butyric acid methyl ester (PC 70 BM) blends using MoO3 -PEDOT:PSS composite fi lm as hole transport layer (HTL) show considerable improvement in power conversion effi ciency (PCE), from 5.5% to 6.4%, compared with the reference pristine PEDOT:PSS-based device. More importantly, the device with MoO3 -PEDOT:PSS HTL shows considerably improved stability, with the PCE remaining at 80% of its original value when stored in ambient air in the dark for 10 days. In comparison, the reference solar cell with PEDOT:PSS layer shows complete failure within 10 days. This MoO3 -PEDOT:PSS implies the potential for low-cost roll-to-roll fabrication of high-effi ciency polymer solar cells with long-term stability at ambient conditions. © 2013 WILEY-VCH Verlag GmbH and Co. © 2013 WILEY-VCH Verlag GmbH & Co.


Xue L.,University of Osnabrück | Han Y.,CAS Changchun Institute of Applied Chemistry
Progress in Materials Science | Year: 2012

Strategies for the inhibition of dewetting of thin polymer films are reviewed. First, a brief introduction to the theory and the dynamics of dewetting of thin polymer films is given. Methods for the inhibition of dewetting of thin polymer films, including the modification of the substrate and the polymer, the cross-linking of the polymer and the addition of an additive as well as their mechanisms for inhibition are discussed. The chemical modification of the substrate or the polymer itself and the phase separation increase the thermodynamic stability of the system, while the cross-linking of the polymers reduces the mobility of the polymer chains, kinetically arresting the dewetting. The addition of an additive appears to thermodynamically and kinetically inhibit the dewetting. Finally, the future outlook in this research field is highlighted. © 2011 Elsevier Ltd. All rights reserved.


Guo Y.-N.,CAS Changchun Institute of Applied Chemistry | Guo Y.-N.,University of Chinese Academy of Sciences | Xu G.-F.,CAS Changchun Institute of Applied Chemistry | Wernsdorfer W.,CNRS Neel Institute | And 6 more authors.
Journal of the American Chemical Society | Year: 2011

The high axiality and Ising exchange interaction efficiently suppress quantum tunneling of magnetization of an asymmetric dinuclear DyIII complex, as revealed by combined experimental and theoretical investigations. Two distinct regimes of blockage of magnetization, one originating from the blockage at individual Dy sites and the other due to the exchange interaction between the sites, are separated for the first time. The latter contribution is found to be crucial, allowing an increase of the relaxation time by 3 orders of magnitude. © 2011 American Chemical Society.


Xue L.,University of Osnabrück | Zhang J.,CAS Changchun Institute of Applied Chemistry | Han Y.,CAS Changchun Institute of Applied Chemistry
Progress in Polymer Science (Oxford) | Year: 2012

Strategies for the utilization of phase separation to generate ordered pattern in polymer thin film are reviewed. First, the fundamental theory and factors influencing phase separation in polymer thin film are discussed. That is followed by a discussion of the formation of ordered patterns induced by phase separation in polymer thin films under the influence of a chemical heterogeneous substrate, convection or breath figures. The mechanisms and the conditions for well-ordered structures generated by phase separation are then discussed to show that multi-scaled/multi-component patterns, stimuli-responsive patterns may be developed by controlling the preparation conditions or exposing the sample to different environments more complex structures. Finally, applications of fabricated patterns in pattern generation and reproduction, antireflecting coating, catalysis, bio-chips and optoelectronics are also discussed. © 2011 Elsevier Ltd.


Fu Z.,Jilin University | Wang X.,Jilin University | Yang Y.,Hebei University | Wu Z.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Dalton Transactions | Year: 2014

Uniform and well-crystallized calcium fluorapatite [Ca5(PO 4)3F, FAP] microrods have been successfully synthesized by a facile one-step hydrothermal synthesis method using sodium citrate as the crystal modifier. X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL), photoluminescent excitation spectra (PLE) and decay studies were employed to characterize the samples. The electronic structure and orbital population of FAP were also determined by means of density functional theory calculations. Under ultraviolet irradiation, the FAP:Tb3+,Eu3+ samples exhibit a blue-light emission of the host matrix, as well as the typical green emission band of the Tb3+ ions, and a red-light emission of Eu 3+. The highly intense red emission bands of the Eu3+ ions were attributed to the effective energy transfer from the Tb3+ to Eu3+ ions, which has been justified through the luminescence spectra and the fluorescence decay dynamics. The luminescence colors of FAP:Tb 3+,Eu3+ microrods can be easily tuned by changing the concentration of Eu3+ ions. The results reveal that the combination of the self-activated luminescence and rare earth-doping emission in FAP:Tb 3+,Eu3+ microrods could result in tunable emission in a large color gamut, which can be used as a potential candidate for white-light-emitting diodes and other display devices. © 2014 The Royal Society of Chemistry.


Sun X.,Oak Ridge National Laboratory | Sun X.,CAS Changchun Institute of Applied Chemistry | Luo H.,Oak Ridge National Laboratory | Dai S.,Oak Ridge National Laboratory | Dai S.,University of Tennessee at Knoxville
Chemical Reviews | Year: 2012

A study was conducted to demonstrate that ionic liquids-based extraction had emerged as a potential strategy for the advanced nuclear fuel cycle (NFC). The advanced NFC maximized fuel resource utilization, reduced the volume and toxicity of nuclear waste, facilitated handling and transportation, and saved on geological repository costs. Room-temperature ionic liquids (ILs), a novel type of solvent, showed significant potential as a separation technology for the advanced NFC. Room-temperature ionic liquids were defined as room-temperature molten salts, which were composed of cations and anions, and their melting points were below 100 °C. The ILs gained significance for their preparation, purification, physicochemical properties, solvation environment, partitioning behavior, and extraction mechanism, along with strategies for improvement and a forecast of IL-based extraction from the viewpoint of promising technologies for the advanced NFC.


Sun J.,CAS Changchun Institute of Applied Chemistry | Yue Y.,Jilin University | Wang P.,CAS Changchun Institute of Applied Chemistry | He H.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of Materials Chemistry C | Year: 2013

We report a direct one-pot approach, employing tetrakis(hydroxymethyl) phosphonium chloride (THPC) and 11-mercaptoundecanoic acid (11-MUA) as combined reducing/capping agents, for the rapid preparation of fluorescent gold nanoclusters (AuNCs) from HAuCl4 in aqueous solution at room temperature. The as-prepared AuNCs exhibit a fluorescence emission at 535 nm, a quantum yield of 1.8% and average diameters of 2.0 ± 0.5 nm. The resultant MUA/THPC-AuNCs have been exploited, for the first time, for the highly sensitive and selective detection of silver ions (Ag+) in aqueous solution when using EDTA as a masking agent for Hg2+. The fluorescence intensity quenches linearly within the range of 25 nM to 3 μM with high sensitivity (LOD = 9 nM, S/N = 3) and this sensing system has been applied for environmental water sample analysis. This journal is © The Royal Society of Chemistry 2013.


Ma D.-L.,CAS Changchun Institute of Applied Chemistry | Ma D.-L.,Jilin University | Cao Z.-Y.,Jilin University | Wang H.-G.,CAS Changchun Institute of Applied Chemistry | And 4 more authors.
Energy and Environmental Science | Year: 2012

A new hybrid nanostructure composed of three-dimensionally ordered macroporous (3DOM) FeF 3 and an homogenous coating of poly(3, 4-ethylenedioxythiophene) (PEDOT) is successfully synthesized using polystyrene (PS) colloidal crystals as hard template, and the coating of PEDOT is achieved through a novel in situ polymerization method. The special nanostructure provides a three-dimensional, continuous, and fast electronic and ionic path in the electrode. Surprisingly, the advantageous combination of 3DOM structure and homogenous coating of PEDOT endows the as-prepared hybrid nanostructures with a stable and high reversible discharge capacity up to 210 mA h g -1 above 2.0 V at room temperature (RT), and a good rate capability of 120 mA h g -1 at a high current density of 1 A g -1, which opens up new opportunities in the development of high performance next-generation lithium-ion batteries (LIBs). © 2012 The Royal Society of Chemistry.


Aoki K.,Toyohashi University of Technology | Fujisawa I.,Toyohashi University of Technology | Murayama K.,Tohoku University | Hu N.-H.,CAS Changchun Institute of Applied Chemistry
Coordination Chemistry Reviews | Year: 2013

Metal ions play a key role in nucleic acid structure and activity. The elucidation of factors/rules that govern the binding of metal ions is therefore an essential step for the better understanding of nucleic acid functions. In this review, we deal with stereospecific intra-molecular interligand interactions as such a factor, involving hydrogen-bonding, electrostatic interaction, and steric constraints, especially focusing on their significance as a factor that could affect base-specific metal bonding to adenine and guanine bases in the solid state. © 2013 Elsevier B.V.


Yang W.,CAS Changchun Institute of Applied Chemistry | Parker T.G.,Florida State University | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry
Coordination Chemistry Reviews | Year: 2015

Uranium phosphonates, an important class of actinide-organic coordination polymers, exhibit an exceptionally diverse and broad range of crystal structures. A variety of structure topologies have been identified for hexavalent uranium phosphonates, including cage clusters, chains, ribbons and tubes, sheets, and three-dimensional frameworks. In contrast, only a handful of tetravalent uranium phosphonates are known. This review presents a comprehensive account of the crystal structures of uranium phosphonates and the various building units (e.g. discrete monomers, polymeric units, infinite chains, and sheets) that result from the numerous coordination modes of phosphonate ligands with uranium. © 2015 Elsevier B.V..


Tong J.,CAS Changchun Institute of Applied Chemistry | Wu Z.,CAS Changchun Institute of Applied Chemistry | Li Y.,Jilin University | Wu D.,Jilin University
Dalton Transactions | Year: 2013

A series of polynuclear superalkali cations YLi3+ (Y = O2, CO4, C2O4, and C 2O6) have been studied using ab initio method. The structural characters and stabilities of these systems are found to be related to the nature of the central cores. In the lowest-energy structure of the C 2O4Li3+ cations, the central group features a slight distortion. While in the global minima of O2Li 3+, CO4Li3+ and C 2O6Li3+ cations, the central cores are divided into various units including one peroxo group (O2). These YLi3+ (Y = O2, CO4, C 2O4, and C2O6) species exhibit very low vertical electron affinities of 3.01-3.85 eV (except one outlier in one of the O2Li3+ species which lie much higher in energy than the most stable structure) and hence should be classified as superalkali cations, and the corresponding neutral species can be regarded as superalkalies. Such polynuclear superalkalies are candidates to the superatoms and offered potential building blocks for the assembly of new materials in which strong electron donors are involved. © 2013 The Royal Society of Chemistry.


Wang Y.,CAS Changchun Institute of Applied Chemistry | Gan L.,CAS Changchun Institute of Applied Chemistry | Wang E.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of Chemical Theory and Computation | Year: 2013

Adenylate kinase (ADK) has been explored widely, through both experimental and theoretical studies. However, still less is known about how the functional dynamics of ADK is modulated explicitly by its natural substrates. Here, we report a quantitative study of the dynamic energy landscape for ADK responding to the substrate binding by integrating both experimental investigations and theoretical modeling. We make theoretical predictions which are in remarkable agreement with the single molecule experiments on the substrate-bound complex. With our combined models of ADK in its apo form, in the presence of AMP or ATP, and in complex with both substrates, we specifically address the following key questions: (1) Are there intermediate state(s) during their catalytic cycle and if so how many? (2) How many pathways are there along the open-to-closed transitions and what are their corresponding weights? (3) How do substrates influence the pathway weights and the stability of the intermediates? (4) Which lid's motion is rate-limiting along the turnover cycle, the NMP or the LID domain? Our models predict two major parallel stepwise pathways and two on-pathway intermediates which are denoted as IN (NMP domain open while LID domain closed) and IL (LID domain open and NMP domain closed), respectively. Further investigation of temperature effects suggests that the IN pathway is dominant at room temperature, but the I L pathway is dominant at the optimal temperature. This leads us to propose that the IL pathway is more dominant by entropy and I N pathway by enthalpy. Remarkably, our results show that even with maximum concentrations of natural substrates, ADK still fluctuates between multiple functional states, reflecting an intrinsic capability of large-scale conformational fluctuations which may be essential to its biological function. The results based on the dual-ligands model provide the theoretical validation of random bisubstrate biproducts (Bi-Bi) mechanism for the enzymatic reaction of ADK. Additionally, the pathway flux analysis strongly suggests that the motion of the NMP domain is the rate-determining step for the conformational cycle (opening and closing). © 2012 American Chemical Society.


Li D.,Jilin University | Liang Z.,Jilin University | Chen J.,CAS Changchun Institute of Applied Chemistry | Yu J.,Jilin University | Xu R.,Jilin University
Dalton Transactions | Year: 2013

A new type of organophosphonic acid, (4,4′-(1,2-diphenylethene-1,2- diyl)bis(4,1-phenylene))bis(methylene)diphosphonic acid (PATPE), based on tetraphenylethene has been prepared, and its ester derivative exhibits the characteristic property of aggregation-induced emission (AIE) in DMSO-H 2O solution. The PATPE is then fabricated into hydroxyapatite by a one-pot condensation process to form hollow mesoporous nanocapsules of ellipsoidal morphology. The AIE luminogen-bridged hollow hydroxyapatite nanocapsules emit strong blue light under UV irradiation, which is further used for drug delivery using ibuprofen (IBU) as a model drug. The fluorescence intensity of the materials varies greatly with the loading and release of IBU, suggesting that the drug release process may be tracked in terms of the change of luminescence intensity. The biocompatibility of AIE luminogen functionalized material is also evaluated on HUH7 human hepatoma cells using the MTT assay. The low cytotoxicity of the materials reveals that the as-prepared multifunctional hydroxyapatite will be a new candidate for simultaneous drug delivery and cell imaging in potential bioapplications. This journal is © The Royal Society of Chemistry 2013.


Jin R.,CAS Changchun Institute of Applied Chemistry | Bian Z.,CAS Changchun Institute of Applied Chemistry | Li J.,Jilin University | Ding M.,CAS Changchun Institute of Applied Chemistry | Gao L.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2013

ZIF-8 crystal coatings were prepared by direct growth on different flexible polyimide substrates including a thin membrane and electrospun nanofiber mat. In SEM pictures, the ZIF-8 crystals exhibit a rhombic dodecahedron morphology. Owing to the flexible polyimide substrate, the MOF-polymer film may be moderately bent or easily tailored when not destroyed. The ZIF-8 coatings can be activated at high temperature owing to the excellent thermal resistance and low coefficient of thermal expansion of the polyimide. Furthermore, this material may be used as an efficient heterogeneous catalyst for the Knoevenagel reaction and can be easily recovered. The ZIF-8 coatings and 2-methylimidazole show similar catalytic behaviour as a weak base. This journal is © 2013 The Royal Society of Chemistry.


Liu Q.-C.,CAS Changchun Institute of Applied Chemistry | Liu Q.-C.,Jilin University | Xu J.-J.,CAS Changchun Institute of Applied Chemistry | Chang Z.-W.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Journal of Materials Chemistry A | Year: 2014

Cobalt oxide nanosheets (Co3O4 NSs) are grown on carbon paper (CP) by an efficient and facile electrodeposition method. When directly used as free-standing cathode for lithium-oxygen batteries, the Co 3O4 NSs/CP is found to be robust and shows enhanced specific capacity and cycling stability. This journal is © the Partner Organisations 2014.


Li W.,Jilin University | Pan Y.,Jilin University | Xiao R.,Jilin University | Peng Q.,Jilin University | And 7 more authors.
Advanced Functional Materials | Year: 2014

In principle, the ratio (Φ) of the maximum quantum efficiencies for electroluminescence (EL) to photoluminescence (PL) can be expected to approach unity, if the exciton (bound electron-hole pair) generated from the recombination of injected electrons and holes in OLEDs has a sufficiently weak binding energy. However, seldom are examples of Φ > 25% reported in OLEDs because of the strongly bound excitons for most organic semiconductors in nature. Here, a twisting donor-acceptor triphenylamine-thiadiazol molecule (TPA-NZP) exhibits fluorescent emission through a hybridized local and charge-transfer excited state (HLCT), which is demonstrated from both fluorescent solvatochromic experiment and quantum chemical calculations. The HLCT state possesses two combined and compatible characteristics: a large transition moment from a local excited (LE) state and a weakly bound exciton from a charge transfer (CT) state. The former contributes to a high-efficiency radiation of fluorescence, while the latter is responsible for the generation of a high fraction of singlet excitons. Using TPA-NZP as the light-emitting layer in an OLED, high Φ values of 93% (at low brightness) and 50% (at high brightness) are achieved, reflecting sufficient employment of the excitons in the OLED. Characterization of the EL device shows a saturated deep-red emission with CIE coordinates of (0.67, 0.32), accompanied by a rather excellent performance with a maximum luminance of 4574 cd m-2 and a maximum external quantum efficiency (ηext) of ∼2.8%. The HLCT state is a new way to realize high-efficiency of EL devices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li L.,CAS Changchun Institute of Applied Chemistry | Li L.,Jilin University | Wu Z.,CAS Changchun Institute of Applied Chemistry | Wu Z.,University of Chinese Academy of Sciences | And 3 more authors.
Energy and Environmental Science | Year: 2014

To meet the rapid development of flexible, portable, and wearable electronic devices, extensive efforts have been devoted to develop matchable energy storage and conversion systems as power sources, such as flexible lithium-ion batteries (LIBs), supercapacitors (SCs), solar cells, fuel cells, etc. Particularly, during recent years, exciting works have been done to explore more suitable and effective electrode/electrolyte materials as well as more preferable cell configuration and structural designs to develop flexible power sources with better electrochemical performance for integration into flexible electronics. An overview is given for these remarkable contributions made by the leading scientists in this important and promising research area. Some perspectives for the future and impacts of flexible energy storage and conversion systems are also proposed. © The Royal Society of Chemistry 2014.


Chen J.,Jilin University | Yi F.-Y.,CAS Changchun Institute of Applied Chemistry | Yu H.,Jilin University | Jiao S.,Jilin University | And 2 more authors.
Chemical Communications | Year: 2014

Detecting volatile amines is a significant topic in the quality control of food and medical diagnosis. We report the first Eu-coordination polymer (CP) as a sensory material for the detection of a class of amine vapors with high selectivity and rapid response. This journal is © the Partner Organisations 2014.


Huang Y.,CAS Changchun Institute of Applied Chemistry | Huang Y.,Jilin University | Huang X.-L.,CAS Changchun Institute of Applied Chemistry | Huang X.-L.,University of Chinese Academy of Sciences | And 4 more authors.
Journal of Materials Chemistry | Year: 2012

A unique ultrathin porous NiO nanosheets/graphene hierarchical structure is successfully fabricated via a facile, effective, and general strategy. The advantageous combination of conducting and flexible graphene and porous and ultrathin NiO nanosheets endows the obtained hybrid with a remarkable lithium-storage performance, including high reversible capacity, good rate capability and cycle performance. © 2012 The Royal Society of Chemistry.


Lin Y.,CAS Changchun Institute of Applied Chemistry | Zhang F.,Shanghai Normal University | Pan D.,CAS Changchun Institute of Applied Chemistry | Li H.,Shanghai Normal University | Lu Y.,University of California at Los Angeles
Journal of Materials Chemistry | Year: 2012

TiO 2/(ZnS) x(CuInS 2) 1-x nanocomposites were prepared from oleic acid-capped TiO 2 nanocrystals and alloyed (ZnS) x(CuInS 2) 1-x nanocrystals. Element mapping and transmission electron microscopy (TEM) results suggested that the nanocomposites exhibit homogeneous composition with uniform mesoporous structure. High photocatalytic activities driven by simulated solar light were achieved owning to their high surface area and efficient electron transfer from (ZnS) x(CuInS 2) 1-x to TiO 2. This work enables the synthesis of a large variety of photocatalysts from nanocrystal building blocks for various applications beyond photodegradation of organic pollutants. © 2012 The Royal Society of Chemistry.


Zhang F.-F.,CAS Changchun Institute of Applied Chemistry | Zhang F.-F.,Shandong University of Technology | Zhang X.-B.,CAS Changchun Institute of Applied Chemistry | Dong Y.-H.,Shandong University of Technology | Wang L.-M.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

A novel sulfur@rGO composite material with a saccule-like structure is synthesized via a facile and effective strategy with an oil in water (O/W) system. The obtained materials exert outstanding electrochemical performance at high rates as a cathode material for rechargeable lithium sulfur cells. © 2012 The Royal Society of Chemistry.


Pang X.,Cornell University | Pang X.,CAS Changchun Institute of Applied Chemistry | Chu C.-C.,Cornell University
Polymer | Year: 2010

A series of new biodegradable hybrid hydrogels were designed and fabricated from a new family of amino acid-based functional poly(ester amide) (PEA-AG) and commercial poly(ethylene glycol) diacrylate (PEG-DA) or Pluronic diacrylate (Pluronic-DA) by UV photocrosslinking. These biodegradable hybrid hydrogels were characterized in terms of equilibrium swelling ratio (Qeq), compression modulus by dynamic mechanical analysis (DMA), and interior morphology by scanning electron microscope (SEM). Both the precursors' chemical structures and feed ratio had significant effect on the properties of the hybrid hydrogels. All these hybrid hydrogels had a three-dimensional porous network structure. The hydrophobicity, crosslinking density and mechanical strength of the hybrid hydrogels increased with an increase in allylglycine (AG) content in the PEA-AG, but the swelling and pore size of the hybrid hydrogels decreased. The biodegradation rate of these hybrid hydrogels in an enzyme (α-chymotrypsin) solution was faster than in a pure PBS buffer control, and the biodegradation rate increased with an increase in α-chymotrypsin concentration and allylglycine content. © 2010.


Liu Z.,CAS Changchun Institute of Applied Chemistry | Dong K.,CAS Changchun Institute of Applied Chemistry | Dong K.,University of Chinese Academy of Sciences | Liu J.,Jilin University | And 3 more authors.
Small | Year: 2014

Nanomaterials have gained considerable attention and interest in the development of novel and high-resolution contrast agents for medical diagnosis and prognosis in clinic. A classical urea-based homogeneous precipitation route that combines the merits of in situ thermal decomposition and surface modification is introduced to construct polyethylene glycol molecule (PEG)-decorated hybrid lutetium oxide nanoparticles (PEG-UCNPs). By utilizing the admirable optical and magnetic properties of the yielded PEG-UCNPs, in vivo up-conversion luminescence and T1-enhanced magnetic resonance imaging of small animals are conducted, revealing obvious signals after subcutaneous and intravenous injection, respectively. Due to the strong X-ray absorption and high atomic number of lanthanide elements, X-ray computed-tomography imaging based on PEG-UCNPs is then designed and carried out, achieving excellent imaging outcome in animal experiments. This is the first example of the usage of hybrid lutetium oxide nanoparticles as effective nanoprobes. Furthermore, biodistribution, clearance route, as well as long-term toxicity are investigated in detail after intravenous injection in a murine model, indicating the overall safety of PEG-UCNPs. Compared with previous lanthanide fluorides, our nanoprobes exhibit more advantages, such as facile construction process and nearly total excretion from the animal body within a month. Taken together, these results promise the use of PEG-UCNPs as a safe and efficient nanoparticulate contrast agent for potential application in multimodal imaging. Clinical noninvasive diagnostic imaging generally holds excellent capability in visualizing and understanding various functions in biologic systems. Using PEGylation hybrid lutetium oxide as a novel nanoparticulate contrast agent, high-resolution tri-modal imaging can be achieved both in vitro and in vivo. Meanwhile, detailed long-term retention and toxicity studies indicate the excellent biocompatibility and overall safety of these well-prepared PEG-UCNPs. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ju E.,CAS Changchun Institute of Applied Chemistry | Ju E.,University of Chinese Academy of Sciences | Liu Z.,CAS Changchun Institute of Applied Chemistry | Du Y.,Jilin University | And 4 more authors.
ACS Nano | Year: 2014

Probes for detecting highly reactive oxygen species (hROS) are critical to both understanding the etiology of the disease and optimizing therapeutic interventions. However, problems such as low stability due to autoxidation and photobleaching and unsuitability for biological application in vitro and in vivo, as well as the high cost and complex procedure in synthesis and modification, largely limit their application. In this work, binary heterogeneous nanocomplexes (termed as C-dots-AuNC) constructed from gold clusters and carbon dots were reported. The fabrication takes full advantages of the inherent active groups on the surface of the nanoparticles to avoid tedious modification and chemical synthetic processes. Additionally, the assembly endowed C-dots-AuNC with improved performance such as the fluorescence enhancement of AuNCs and stability of C-dots to hROS. Moreover, the dual-emission property allows sensitive imaging and monitoring of the hROS signaling in living cells with high contrast. Importantly, with high physiological stability and excellent biocompatibility, C-dots-AuNC allows for the detection of hROS in the model of local ear inflammation. © 2014 American Chemical Society.


Shih Z.-Y.,National Taiwan University | Wang C.-W.,National Taiwan University | Xu G.,CAS Changchun Institute of Applied Chemistry | Chang H.-T.,National Taiwan University
Journal of Materials Chemistry A | Year: 2013

A facile method has been demonstrated for the preparation of PdCu nanoparticles (NPs) with various morphologies from Pd2+ and Cu 2+ reduced by ascorbate in the presence of dodecyltrimethylammonium chloride (DTAC) at 95 °C. We have found that DTAC is important to assist the growth of PdCu with high-energy surfaces through the etching and capping of certain surfaces of Pd and PdCu seeds. By varying the Pd2+/Cu 2+ molar ratio, different morphologies of PdCu NPs have been prepared. Cubic PdCu NPs have a dominant Pd3Cu composition when prepared at a high Pd2+/Cu2+ molar ratio (20/1), while porous PdCu NPs have a dominant PdCu3 composition when prepared at a low Pd2+/Cu2+ molar ratio (1/10). The copper content not only controls the morphology, but also affects the catalytic activity toward the methanol oxidation reaction (MOR) in alkaline media. Upon increasing the copper content, the catalytic activity toward the MOR increases, mainly due to the advantages of the electroactive surface area, more direct cathodic oxide reduction (lower onset potential for the formation of Pd-OH), and synergistic effects. Porous PdCu NP-modified electrodes provide a higher catalytic activity (363 A g-1) toward the MOR at a more negative onset potential (-0.62 V vs. Ag/AgCl) on the porous PdCu electrodes than commercial Pd/C-modified ones do (180 A g-1) at -0.52 V. To the best of our knowledge, this is the first example using porous PdCu NP-modified electrodes as anodes under alkaline conditions in direct methanol fuel cells (DMFCs). With the advantages of high electrochemical activity, stability, and cost effectiveness, the porous PdCu NPs have great potential as anode catalysts for DMFCs. © The Royal Society of Chemistry 2013.


Wang H.-G.,CAS Changchun Institute of Applied Chemistry | Yuan S.,CAS Changchun Institute of Applied Chemistry | Yuan S.,Jilin University | Ma D.-L.,CAS Changchun Institute of Applied Chemistry | And 5 more authors.
Advanced Energy Materials | Year: 2014

Organic tailored materials using various aromatic carbonyl derivative polyimides are synthesized by tuning the alteration of the conjugated backbone. These materials are used as the cathodes for high-power, long-cycle, and sustainable sodium-organic batteries. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang P.,CAS Changchun Institute of Applied Chemistry | Jiang T.,Jilin University | Zhu C.,CAS Changchun Institute of Applied Chemistry | Zhai Y.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Nano Research | Year: 2010

The synthesis of graphene-semiconductor nanocomposites has attracted increasing attention due to their interesting optoelectronic properties. However the synthesis of such nanocomposites, with decorated particles well dispersed on graphene, is still a great challenge. This work reports a facile, one-step, solvothermal method for the synthesis of graphene-CdS and graphene-ZnS quantum dot nanocomposites directly from graphene oxide, with CdS and ZnS very well dispersed on the graphene nanosheets. Photoluminescence measurements showed that the integration of CdS and ZnS with graphene significantly decreases their photoluminescence. Transient photovoltage studies revealed that the graphene-CdS nanocomposite exhibits a very unexpected strong positive photovoltaic response, while separate samples of graphene and CdS quantum dots (QDs) of a similar size do not show any photovoltaic response. © The Author(s) 2010.


Zhang J.,CAS Shenyang Institute of Metal Research | Su D.S.,CAS Shenyang Institute of Metal Research | Blume R.,Fritz Haber Institute of the Max Planck Society | Schlogl R.,Fritz Haber Institute of the Max Planck Society | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2010

Hard core: A hybrid catalyst system for dehydrogenation of ethylbenzene comprises nanoparticles consisting of nanodiamond cores and highly curved, defective graphene shells (see picture). The system exhibits high catalytic activity and selectivity over a long period of time. In contrast to industrial K-promoted Fe catalysts, steam decoking of the catalyst is not required. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jian Z.,CAS Changchun Institute of Applied Chemistry | Jian Z.,University of Chinese Academy of Sciences | Tang S.,Jilin University | Cui D.,CAS Changchun Institute of Applied Chemistry
Macromolecules | Year: 2011

By using the cationic lutetium allyl species (C 5Me 4-C 5H 4N)Lu(η 3-C 3H 5) 2 (1)/[Ph 3C][B(C 6F 5) 4], the copolymerization of isoprene (IP) with styrene (St) could be achieved in a full range of monomer feed ratios (10 mol %-90 mol %). The 13C NMR and DSC analyses, and the competitive polymerization ratios (r St = 3.1 vs r IP = 23.9) clearly revealed that the obtained IP-St copolymers were multiblocked microstructure with high cis-1,4-polyisoprene (PIP) units (80%) and crystalline syndiotactic polystyrene (sPS) sequences, which was in contrast to the copolymerization behavior of butadiene (BD) and St with the same system that afforded only diblock copolymer. Strikingly, the terpolymerization of St with IP and BD via coordination mechansim was realized for the first time with high conversions (74-85%) and high activities (111-144 kg (mol Lu h) -1). The 13C NMR spectroscopic analysis indicated that the resultant terpolymers were composed of perfect sPS blocks, high cis-1,4-PIP units (77.7%) and almost pure cis-1,4-polybutadiene (PBD) sequences (97.5%) arranged in multiblocked mode. The insertion rate of styrene monomer in the terpolymer could be tuned swiftly by changing its feed ratio. DSC curves suggested that these multiblock terpolymers had continuously variable but single T g and (or) T m values, which was different from the triblock IP-BD-St terpolymer having two distinct T g values (-105 and -57 °C) and one high T m value (265 °C). Such novel terpolymers could not be accessed by any other methods known to date. © 2011 American Chemical Society.


Zhang J.,Jilin University | Lu Z.-Y.,CAS Changchun Institute of Applied Chemistry | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2011

By using computer simulations, we propose a simple route to fabricate 7-17 nm particles with controllable patch symmetry via self-assembly of a polymer chain in one step. A single chain of polystyrene-polymethylmethacrylate (PS-PMMA) multiblock copolymer, which is intended to be a generic representative for common hydrophobic multiblock copolymers, is used to fabricate the patchy particles in a solvent that is poor for both components. Various kinds of patchy particles, such as one-patch (with C ∞v symmetry), two-patch (with D ∞h symmetry), three-patch (with D 3hsymmetry), four-patch (with T d symmetry), and cross-ribbon patchy particles, have been obtained. Our work demonstrates that a rational bottom-up design of patchy nanoparticles with controllable symmetry is possible by manipulating the block copolymer chain length and solvent quality. © 2011 The Royal Society of Chemistry.


Sun X.,Oak Ridge National Laboratory | Sun X.,CAS Changchun Institute of Applied Chemistry | Luo H.,Oak Ridge National Laboratory | Dai S.,Oak Ridge National Laboratory | Dai S.,University of Tennessee at Knoxville
Talanta | Year: 2012

Three functionalized ionic liquids (ILs), tetrabutylammonium di(2-ethylhexyl)phosphate ([TBA][DEHP]), trioctylmethylammonium di(2-ethylhexyl)phosphate ([TOMA][DEHP]), and trihexyl(tetradecyl)phosphonium di(2-ethylhexyl)phosphate ([THTP][DEHP]), are synthesized and characterized. These ILs are used as DEHP-based ionic extractants and are investigated for rare earth elements (REEs) separation in 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C 6mim][NTf 2]) and diisopropylbenzene (DIPB) along with di(2-ethylhexyl)phosphoric acid (HDEHP). Solubilities of the DEHP-based ionic extractants in [C 6mim][NTf 2] are much better than that of HDEHP in [C 6mim][NTf 2]. We herein report the achievement of enhanced extractabilities and selectivities for separation of REEs using DEHP-based ionic extractants in [C 6mim][NTf 2]. This work highlights the potential of developing a comprehensive ionic liquid-based extraction strategy for REEs using ionic liquids as both extractant and diluent. © 2011 Elsevier B.V. All rights reserved.


Zhang J.,Jilin University | Lu Z.-Y.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2012

The influence of deformability of two-patch particles on their self-assembly behavior is studied via computer simulations. The softness and the deformability of the patchy particles can be controlled by varying the cross-linking densities in different parts of the particles. The patchy particles in a solvent that is bad for patches but good for the matrix form linear thread-like structures when cross-linking densities are low, whereas they form three-dimensional network structures at relatively high cross-linking densities. For patchy particles in a solvent that is good for patches but bad for the matrix, inter-connected membrane structures are obtained at relatively low cross-linking densities, and some cluster structures emerge when cross-linking densities are high. Bicontinuous membranes with better morphologies can be observed by tuning the cross-linking densities of different parts of the patchy particles. © The Royal Society of Chemistry.


Li Z.-W.,CAS Changchun Institute of Applied Chemistry | Lu Z.-Y.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry | An L.-J.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2012

Janus particles exhibit interesting self-assembly behavior and functional performances. In particular, soft and deformable Janus particles, as diverse as Janus micelles, Janus microgels, and Janus dendrimers, should receive more attention due to their unique chemical and physical properties and enormous potential applications. Gaining control over precise and predictable self-assembled structures and understanding the fundamental details of self-assembly remain a formidable challenge. Here we present a novel mesoscale model for soft Janus particles, which successfully reflects their physical nature by directly mapping onto experimentally measurable particle properties. By properly tuning Janus balance and the strength of attraction between attractive patches, soft Janus particles can reversibly self-assemble into a number of fascinating hierarchical superstructures in dilute solutions, such as micelles, wormlike strings, single helices, double helices, bilayers, tetragonal bilayers, and complex supermicelles. Our work demonstrates that soft Janus particles with deformable and non-centrosymmetric characteristics hide many surprises in the design and fabrication of hierarchically self-assembled superstructures. © 2012 The Royal Society of Chemistry.


Liu Y.,Jilin University | Liu S.,CAS Changchun Institute of Applied Chemistry | Liu Z.,CAS Changchun Institute of Applied Chemistry
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2013

Xanthine oxidase (XOD) inhibitors play an important role in the treatment of gout and many other diseases related to the superoxide anion metabolism. In this study, an ultrafiltration-liquid chromatography-mass spectrometry (UF-LC-MS) method was developed for the screening and identification of potential XOD inhibitors from Radix Salviae Miltiorrhizae extract. Eleven lipophilic diterpenoid quinines were identified as XOD inhibitors from the extract. The relationship between the structure and activity of the detected compounds was estimated on the basis of the UF-LC-MS data. The results demonstrate that the 1,2-naphthoquinone group is necessary for the XOD inhibitory activity of the compounds, and that furan and hydroxyl on the alicyclic ring could enhance the activity of the compounds at different levels. These results may explain and support the medical use of the extract of Radix S. Miltiorrhizae for the prevention and treatment of hyperuricemia and gout. © 2013 Elsevier B.V.


Tong S.,Jilin University | Liu Q.,Jilin University | Li Y.,Jilin University | Zhou W.,Jilin University | And 2 more authors.
Journal of Chromatography A | Year: 2012

Novel monolithic capillary columns with embedded graphene were developed and used for polymer monolith microextraction (PMME) coupled to LC-MS analysis. The column was prepared inside fused silica capillaries (320μm, i.d.) using thermally initiated free-radical polymerization with butyl methacrylate (BMA) as monomer, ethylene dimethacrylate (EDMA) as cross-linker, and 1,4-butanediol and 1-propanol as porogens. Graphene (GN) was incorporated into the poly(BMA-EDMA) monolith to enhance the loading capacity. The obtained GN and the poly(BMA-EDMA-GN) monolith were characterized by transmission electron microscope (TEM), atomic force microscopic (AFM) and scanning electron microscopy (SEM). The extraction performance of the monolithic column was evaluated by glucocorticoids (GCs) as the analytes. The operation parameters of PMME including desorption solvent, sample flow rate, sample volume, sample pH, and eluent flow rate were studied and optimized. When compared to the parent poly(BMA-EDMA) column and direct sample analysis, high enrichment capacity was observed in the case of GN-entrapped monolith. The GN incorporated monolithic capillary showed satisfactory reusability and stability during extraction. The limits of detection (S/N. =3) for nine GCs were in the range of 0.13-1.93. ng/mL. Relative standard deviations for the determination of the target GCs were less than 14.5%. Finally, the PMME method, based on the developed monolithic capillary as the extraction media, was successfully applied to the determination of nine GCs in cosmetics. The recoveries of GCs spiked in different matrices ranged from 83.7% to 103.8%. © 2012 Elsevier B.V.


Liu Y.,CAS Changchun Institute of Applied Chemistry | Ai K.,CAS Changchun Institute of Applied Chemistry | Liu J.,Jilin University | Yuan Q.,Jilin University | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

Enlightening particles: A contrast agent for invivo X-ray computed tomography (CT) imaging is composed of an Yb-based nanoparticle (NP) that is stabilized with oleic acid and modified with the biocompatible polymer DSPE-PEG 2000 (see picture). The contrast agent exhibits long circulation time invivo and low toxicity and is also much more effective than a clinical iodinated agent. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang Y.,CAS Changchun Institute of Applied Chemistry | Song S.,CAS Changchun Institute of Applied Chemistry | Liu J.,Jilin University | Liu D.,CAS Changchun Institute of Applied Chemistry | Zhang H.,CAS Changchun Institute of Applied Chemistry
Angewandte Chemie - International Edition | Year: 2015

Limited therapeutic efficiency and severe side effects in patients are two major issues existing in current chemotherapy of cancers in clinic. To design a proper theranostic platform seems thus quite needed to target cancer cells accurately by bioimaging and simultaneously release drugs on demand without premature leakage. A novel ZnO-functionalized upconverting nanotheranostic platform has been fabricated for clear multi-modality bioimaging (upconversion luminescence (UCL), computed tomography (CT), and magnetic resonance imaging (MRI)) and specific pH-triggered on-demand drug release. In our theranostic platform multi-modality imaging provides much more detailed and exact information for cancer diagnosis than single-modality imaging. In addition, ZnO can play the role of a "gatekeeper" to efficiently block the drug in the mesopores of the as-prepared agents until it is dissolved in the acidic environment around tumors to realize sustained release of the drug. More importantly, the biodegradable ZnO, which is non-toxic against normal tissues, endows the as-prepared agents with high therapeutic effectiveness but very low side effects. These findings are of great interests and will inspire us much to develop novel effective imaging-guided on-demand chemotherapies in cancer treatment. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.


Ding R.,CAS Changchun Institute of Applied Chemistry | Ding R.,University of Chinese Academy of Sciences | Ding R.,Jilin University | Qi L.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Nanoscale | Year: 2014

Mesoporous spinel nickel cobaltite (NiCo2O4) nanostructures were synthesized via a facile chemical deposition method coupled with a simple post-annealing process. The physicochemical properties were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. The electrocatalytic performances were investigated by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) tests. The obtained NiCo 2O4 materials exhibit typical agglomerate mesoporous nanostructures with a large surface area (190.1 m2 g-1) and high mesopore volume (0.943 cm3 g-1). Remarkably, the NiCo2O4 shows much higher catalytic activity, lower overpotential, better stability and greater tolerance towards urea electro-oxidation compared to those of cobalt oxide (Co3O 4) synthesized by the same procedure. The NiCo2O 4 electrode delivers a current density of 136 mA cm-2 mg-1 at 0.7 V (vs. Hg/HgO) in 1 M KOH and 0.33 M urea electrolytes accompanied with a desirable stability. The impressive electrocatalytic activity is largely ascribed to the high intrinsic electronic conductivity, superior mesoporous nanostructures and rich surface Ni active species of the NiCo 2O4 materials, which can largely boost the interfacial electroactive sites and charge transfer rates for urea electro-oxidation, indicating promising applications in future wastewater remediation, hydrogen production and fuel cells. © 2013 The Royal Society of Chemistry.


Du Z.-J.,CAS Changchun Institute of Applied Chemistry | Du Z.-J.,University of Chinese Academy of Sciences | Gao L.-X.,CAS Changchun Institute of Applied Chemistry | Lin Y.-J.,Jilin University | Han F.-S.,CAS Changchun Institute of Applied Chemistry
ChemCatChem | Year: 2014

A protocol for the copper-mediated direct aryl C - H halogenation is presented. Highly selective mono- and di-halogenations are achieved by using acyl hypohalites, generated in situ from the readily available carboxylic acid and N-halosuccinimides (NXS; X=Br and Cl) as powerful halogenating reagents. The correct choice of carboxylic acid additives and solvents is essential for both high yield and selectivity. Consequently, the use of inexpensive Cu catalyst and the new strategy for the in situ generation of acyl hypohalite halogenating reagents from the readily affordable and easily-to-handle carboxylic acid and NXS (X=Br and Cl) offers advantages for practical application. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ding R.,CAS Changchun Institute of Applied Chemistry | Ding R.,University of Chinese Academy of Sciences | Ding R.,Jilin University | Qi L.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Catalysis Science and Technology | Year: 2013

Mesoporous spinel NiCo2O4 nanoparticles were synthesized via a simple hydrothermal strategy. Their physicochemical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy-energy dispersive X-ray spectra (SEM-EDS), X-ray photoelectron spectra (XPS) and nitrogen sorption measurements. Their electrocatalytic performances were investigated by cyclic voltammetry (CV), chronoamperomerty (CA) and electrochemical impedance spectroscopy (EIS) tests. The obtained NiCo2O4 materials exhibit a particle size of about 200 nm, a specific surface area (SSA) of 88.94 m2 g-1 and a mesopore volume of 0.195 cm3 g-1. The binary electroactive sites of Co and Ni species, high electron conductivity and intriguing mesoporous structures of the NiCo2O4 electrode favor its desirable electro-catalytic activity. A current density of 93 mA cm-2 at 0.6 V in 1 M KOH and 0.5 M CH3OH electrolytes was obtained for CH3OH electro-oxidation, and a current density of 130 mA cm -2 at -0.3 V in 3 M NaOH and 0.5 M H2O2 electrolytes was achieved for H2O2 electro-reduction. Moreover, the NiCo2O4 electrode exhibits a high stability for both catalytic reactions, showing the potential for further development of high performance non-Pt catalysts based alkaline fuel cells (AFCs). This journal is © The Royal Society of Chemistry.


Sun W.,University of Washington | Yu J.,University of Washington | Deng R.,CAS Changchun Institute of Applied Chemistry | Rong Y.,University of Washington | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2013

Bright dots: Semiconducting polymer dots (Pdots) doped with europium complexes possess line-like fluorescence emission, high quantum yield, and long fluorescence lifetime. The Pdots successfully labeled receptors on cells. The long fluorescence lifetime of the Pdots was used to distinguish them from other red fluorescence emitting nanoparticles, and improve the signal-to-noise ratio for time-gated cellular imaging. PVK=poly(9-vinylcarbazole). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu Y.,CAS Changchun Institute of Applied Chemistry | Liu Y.,Chinese Academy of Sciences | Ai K.,CAS Changchun Institute of Applied Chemistry | Yuan Q.,Jilin University | Lu L.,CAS Changchun Institute of Applied Chemistry
Biomaterials | Year: 2011

We report here the development of Gd-doped ZnO quantum dots (QDs) as dual modal fluorescence and magnetic resonance imaging nanoprobes. They are fabricated in a simple, versatile and environmentally friendly method, not only decreasing the difficulty and complexity, but also avoiding the increase of particle's size brought about by silica coating procedure in the synthesis of nanoprobes reported previously. These nanoprobes, with exceptionally small size and enhanced fluorescence resulting from the Gd doping, can label successfully the HeLa cells in short time and present no evidence of toxicity or adverse affect on cell growth even at the concentration up to 1 mm. These results show that such nanoprobes have low toxicity, especially in comparison with the traditional PEGylated CdSe/ZnS or CdSe/CdS QDs. In MRI studies, they exert strong positive contrast effect with a large longitudinal relaxivity (r 1) of water proton of 16 mm -1 s -1. Their capability of imaging HeLa cells with MRI implies that they have great potential as MRI contrast agents. Combining the high sensitivity of fluorescence imaging with high spatial resolution of MRI, We expect that the as-prepared Gd-doped Zno QDs can provide a better reliability of the collected data and find promising applications in biological, medical and other fields. © 2010 Elsevier Ltd.


Zhang J.,Jilin University | Lu Z.-Y.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry
Soft Matter | Year: 2013

We study the influence of solvent conditions and the chain backbone stiffness of an amphiphilic multiblock copolymer on its self-assembly structures in dilute solution with Brownian dynamics simulations. Various interesting structures, such as single-flower micelle, multi-flower micelle, and single or multi-bridge structures, are observed. In general, highly hydrophobic components benefit the formation of flower micelle structures, while semi-flexible chains are prone to forming bridge structures. We also study the influence of the ratio between hydrophobic and hydrophilic components on self-assembly structures. From our phase diagram, we find that a high component ratio for the hydrophobic blocks favors the formation of micelles with various structural patterns. A single to multi-flower transition is observed by increasing the chain length of the multiblock copolymer. Well-defined multicompartment wormlike micelles can be obtained from pre-assembled flower micelles in a solvent that is poor for both components. This journal is © The Royal Society of Chemistry 2013.


Hensel Z.,Johns Hopkins University | Feng H.,State University of New York at Stony Brook | Han B.,State University of New York at Stony Brook | Hatem C.,Johns Hopkins University | And 4 more authors.
Nature Structural and Molecular Biology | Year: 2012

Gene expression is inherently stochastic; precise gene regulation by transcription factors is important for cell-fate determination. Many transcription factors regulate their own expression, suggesting that autoregulation counters intrinsic stochasticity in gene expression. Using a new strategy, cotranslational activation by cleavage (CoTrAC), we probed the stochastic expression dynamics of cI, which encodes the bacteriophage Î repressor CI, a fate-determining transcription factor. CI concentration fluctuations influence both lysogenic stability and induction of bacteriophage Î. We found that the intrinsic stochasticity in cI expression was largely determined by CI expression level irrespective of autoregulation. Furthermore, extrinsic, cell-to-cell variation was primarily responsible for CI concentration fluctuations, and negative autoregulation minimized CI concentration heterogeneity by counteracting extrinsic noise and introducing memory. This quantitative study of transcription factor expression dynamics sheds light on the mechanisms cells use to control noise in gene regulatory networks. © 2012 Nature America, Inc. All rights reserved.


Liu Y.,CAS Changchun Institute of Applied Chemistry | Liu Y.,University of Chinese Academy of Sciences | Ai K.,CAS Changchun Institute of Applied Chemistry | Liu J.,Jilin University | And 3 more authors.
Advanced Materials | Year: 2013

A new generation of photothermal therapeutic agents based on biopolymer dopamine-melanin colloidal nanospheres is described. Benefitting from their naturally wide distribution in humans, dopamine-melanin colloidal nanospheres exhibit robust biocompatibility and biodegradability, and provide up to 40% photothermal conversion efficiency. After administration, they can efficiently damage tumors at low power density and short irradiation time without damaging healthy tissues. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu Z.,CAS Changchun Institute of Applied Chemistry | Liu Z.,University of Chinese Academy of Sciences | Pu F.,CAS Changchun Institute of Applied Chemistry | Huang S.,Jilin University | And 3 more authors.
Biomaterials | Year: 2013

Due to their unique electric, magnetic, and optical properties, engineered nanostructures have been applied to provide diagnostic, therapeutic, as well as prognostic information about the status of disease. In this study, we report a multifunctional nanoprobe based on PEGylated Gd2O3:Yb3+, Er3+ nanorods (denoted as PEG-UCNPs) for in vivo up-conversion luminescence (UCL), T1-enhanced magnetic resonance (MR), and X-ray computed tomography (CT) multi-modality imaging. A facile and large-scale hydrothermal system combining the merits of an in situ thermal decomposition method and a surface-modified approach is introduced to construct high-quality PEG-UCNPs. By grafting PEG molecules on the surface of PEG-UCNPs, the nanostructures possess excellent stability against in vivo environment and hold long blood circulation time. Cell-cytotoxicity assay, hemolyticity, as well as post-injection histology, hematology, and inflammation analysis further demonstrate their non-cytotoxic character and indicate further in vivo application. In detail, the capability of PEG-UCNPs as high-performance contrast agents for UCL/MR/CT imaging is evaluated successfully through small-animal experiments. Additionally, pharmacokinetics, biodistribution, and clearance route are studied after intravenous injection in a mouse model, reflecting their overall safety. © 2012 Elsevier Ltd.


Chen K.,CAS Changchun Institute of Applied Chemistry | Yin S.,Tohoku University | Xue D.,CAS Changchun Institute of Applied Chemistry
Nanoscale | Year: 2015

A new "combinatorial transition-metal cation pseudocapacitor" was demonstrated by designing combinatorial transition-metal cation pseudocapacitors with binary AxB1-x salt electrodes involving manganese, iron, cobalt, and nickel cations in an alkaline aqueous electrolyte. Binary multi-valence cations were crystallized in the colloidal state through an in situ coprecipitation under an electric field. These electroactive colloids absorbed by carbon black and the PVDF matrix are highly redox-reactive with high specific capacitance values, where the specific electrode configuration can create short ion diffusion paths to enable fast and reversible Faradaic reactions. This work shows huge promise for developing high-performance electrical energy storage systems via designing the colloidal state of electroactive cations. Multiple redox cations in the colloidal state can show high redox activities, making them more suitable for potential application in pseudocapacitor systems. © 2015 The Royal Society of Chemistry.


Zhang Z.,Jilin University | Duan H.,Jilin University | Li S.,CAS Changchun Institute of Applied Chemistry | Lin Y.,Jilin University
Langmuir | Year: 2010

The synthesis and characterization of carbon-coated ferromagnetic nanoparticles that organize into 1-D assemblies of micrometer-sized ferromagnetic chains is described. A controlled aromatization and carbonization of glucose under hydrothermal reaction conditions enabled the preparation of carbonaceous surfactants that were used as shells for the coating of ferromagnetic Fe3O4 nanospheres with a uniform size distribution. Under controlled experimental conditions, it was, for the first time, demonstrated that glucose could be employed as the carbon source in the preparation of continuous 1-D carbon nanoparticle chains with magnetic nanosphere inclusions. The functional groups on the carbon surface will facilitate the linkage of functional groups or catalytic species to the surface in future application. The salient feature of the reported method was the assembly of magnetic nanospheres under hydrothermal reaction conditions in the absence of external fields. © 2010 American Chemical Society.


Liu F.,CAS Changchun Institute of Applied Chemistry | Liu F.,University of Chinese Academy of Sciences | He X.,CAS Changchun Institute of Applied Chemistry | He X.,Changchun University of Science and Technology | And 4 more authors.
Biomaterials | Year: 2013

Here, we report the covalently conjugation of lanthanide doped NaGdF4:Yb3+, Er3+@NaGdF4 upconverting nanoparticles (UCNPs) on methylphosphonate functionalized silica nanospheres (pSi NPs) for invivo upconversion luminescence (UCL), T1-weighted magnetic resonance (MR), and X-ray computed tomography (CT) multi-modality imaging. The nanocomposites (pSi@UCNPs) were synthesized by a facile ligand exchange strategy. The hydrophobic pSi@UCNPs were transferred into aqueous solution by surface coating Pluronic F127. The Pluronic F127 coated pSi@UCNPs (pSi@UCNPs@F127) exhibitexcellent stability in biological medium, inappreciable cytotoxicity and negligible organ toxicity. The pSi@UCNPs@F127 also shows brighter UCL, and higher CT/MR enhancements than that of Pluronic F127 coated NaGdF4:Yb3+, Er3+@NaGdF4 UCNP. In detail, the capability of pSi@UCNPs@F127 as high performance contrast agents for invivo multi-modality (UCL/MR/CT) imaging is evaluated successfully through small-animal experiments. © 2013 Elsevier Ltd.


Chen Y.,CAS Changchun Institute of Applied Chemistry | Chen Y.,Jilin University | Qu K.,CAS Changchun Institute of Applied Chemistry | Zhao C.,CAS Changchun Institute of Applied Chemistry | And 4 more authors.
Nature Communications | Year: 2012

Both human telomeric G-rich and C-rich DNA have been considered as specific drug targets for cancer therapy. However, due to i-motif structure instability and lack of specific binding agents, it remains unclear whether stabilization of telomeric i-motif can inhibit telomerase activity. Single-walled carbon nanotubes (SWNTs) have been reported as the first ligand that can selectively stabilize human telomeric i-motif DNA. Here we report that SWNTs can inhibit telomerase activity through stabilization of i-motif structure. The persistence of i-motif and the concomitant G-quadruplex eventually leads to telomere uncapping and displaces telomere-binding proteins from telomere. The dysfunctional telomere triggers DNA damage response and elicits upregulation of p16 and p21 proteins. This is the first example that SWNTs can inhibit telomerase activity and interfere with the telomere functions in cancer cells. These results provide new insights into understanding the biomedical effects of SWNTs and the biological importance of i-motif DNA. © 2012 Macmillan Publishers Limited. All rights reserved.


Li H.M.,Jilin University | Sun D.Q.,Jilin University | Cai X.L.,CAS Changchun Institute of Applied Chemistry | Dong P.,Jilin University | Wang W.Q.,Jilin University
Materials and Design | Year: 2012

Laser welding of TiNi shape memory alloy wire to stainless steel wire using Ni interlayer was investigated. The results indicated that the Ni interlayer thickness had great effects on the chemical composition, microstructure, gas-pore susceptibility and mechanical properties of laser-welded joints. With an increase of Ni interlayer thickness, the weld Ni content increased and the joint properties increased due to decreasing brittle intermetallic compounds (TiFe2 and TiCr2). The joint fracture occurred in the fusion zone with a brittle intermetallic compound layer. The tensile strength and elongation of the joints reached the maximum values (372MPa and 4.4%) when weld Ni content was 47.25wt.%. Further increasing weld Ni content resulted in decreasing the joint properties because of forming more TiNi3 phase, gas-pores and shrinkage cavities in the weld metals. It is necessary to select suitable Ni interlayer thickness (weld composition) for improving the mechanical properties of laser-welded joints. © 2012 Elsevier Ltd.


Li H.-W.,Jilin University | Li H.-W.,CAS Changchun Institute of Applied Chemistry | Ai K.,CAS Changchun Institute of Applied Chemistry | Wu Y.,Jilin University
Chemical Communications | Year: 2011

An efficient, rapid, and fluorescence visual method for column separation of BSA-protected gold-nanoclusters was proposed based on the dansylation of BSA. After optimization, this procedure can be extended to the separation of any other macromolecule-protected noble metal bioconjugates. © 2011 The Royal Society of Chemistry.


Zhang Z.,CAS Changchun Institute of Applied Chemistry | Xu F.,CAS Changchun Institute of Applied Chemistry | Yang W.,CAS Changchun Institute of Applied Chemistry | Guo M.,Jilin University | And 3 more authors.
Chemical Communications | Year: 2011

Ag-graphene composite nanosheets (AGCN) with adjustable size and well-controlled densities of Ag nanoparticles (Ag NPs) using Poly(N-vinyl-2-pyrrolidone) (PVP) as a reductant and stabilizer are reported. The obtained AGCN substrate is extremely suitable for surface-enhanced Raman spectroscopy (SERS). © 2011 The Royal Society of Chemistry.


Wang Y.,CAS Changchun Institute of Applied Chemistry | Tang C.,CAS Wuhan Institute of Physics and Mathematics | Wang E.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
PLoS Computational Biology | Year: 2012

An increasing number of biological machines have been revealed to have more than two macroscopic states. Quantifying the underlying multiple-basin functional landscape is essential for understanding their functions. However, the present models seem to be insufficient to describe such multiple-state systems. To meet this challenge, we have developed a coarse grained triple-basin structure-based model with implicit ligand. Based on our model, the constructed functional landscape is sufficiently sampled by the brute-force molecular dynamics simulation. We explored maltose-binding protein (MBP) which undergoes large-scale domain motion between open, apo-closed (partially closed) and holo-closed (fully closed) states responding to ligand binding. We revealed an underlying mechanism whereby major induced fit and minor population shift pathways co-exist by quantitative flux analysis. We found that the hinge regions play an important role in the functional dynamics as well as that increases in its flexibility promote population shifts. This finding provides a theoretical explanation of the mechanistic discrepancies in PBP protein family. We also found a functional "backtracking" behavior that favors conformational change. We further explored the underlying folding landscape in response to ligand binding. Consistent with earlier experimental findings, the presence of ligand increases the cooperativity and stability of MBP. This work provides the first study to explore the folding dynamics and functional dynamics under the same theoretical framework using our triple-basin functional model. © 2012 Wang et al.


Ding R.,CAS Changchun Institute of Applied Chemistry | Ding R.,University of Chinese Academy of Sciences | Ding R.,Jilin University | Qi L.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Electrochimica Acta | Year: 2013

Highly porous nickel cobaltite (NiCo2 O4) materials have been synthesized via a facile and scalable chemical synthesis route. The obtained NiCo2O4 material displays a typical secondary submicron/micron-sized (0.1-2 μm) agglomerate morphology, exhibiting large surface area (190.1 m2g-1) and high porosity (1.136cm 3 g-1). The fabricated NiCo2O4 electrode shows high specific capacitance (351 Fg-1 at 1 Ag-1) and high-rate capability (82.1% capacitance retention at 8Ag-1), which is superior to many reported NiCo2O4 materials. Further, the assembled AC-NiCo2O4 aqueous hybrid capacitor exhibits high power and energy densities (2805 Wkg-1, 6.8Whkg-1 at 8Ag -1)and high cycling stability (15% loss after 5000 cycles at 1.5 Ag-1). The high-performance of the NiCo2O4 materials is attributed to their large surface area and highly porous structure which contribute to rich surface electroactive sites and easy ions transport pathways for facile electrochemical reactions. © 2013 Elsevier Ltd. All rights reserved.


Wang W.,Jilin University | Ma D.,CAS Changchun Institute of Applied Chemistry | Gao Q.,Jilin University
IEEE Transactions on Electron Devices | Year: 2012

We demonstrated a low-operation-voltage pentacene organic thin-film transistor (OTFT) with an ultrathin polymer poly(methyl methacrylate co glycidyl methacrylate) as the gate dielectric layer. Under illumination, the threshold voltage (VT) continuously shifted positively, and the operation current (IDS) successively increased with the applied circular gate voltage (VG). After the light switchoff, both V T and $I \rm DS decayed to a metastable state and remained for a long time before decaying back to the initial value. This OTFT has a potential application in a photodetector with nonvolatile memory effect or in a memory by optical programming (P) and electrical erasing (E). The $I \rm DS was turned into a large value (one state) after P by a positive V G pulse under illumination and quickly returned to a small initial value (zero state) after E by a negative V G pulse. The present OTFT fabricated by a simple fabrication process exhibits a good practical foreground due to the low operation voltage and the good repeatability. © 2012 IEEE.


Yang D.,CAS Changchun Institute of Applied Chemistry | Dai Y.,CAS Changchun Institute of Applied Chemistry | Liu J.,Jilin University | Zhou Y.,Jilin University | And 4 more authors.
Biomaterials | Year: 2014

A new type of drug-delivery system (DDS) was constructed, in which the anti-cancer drug doxorubicin (DOX) was conjugated to the ultra-small sized (sub-10nm) BaGdF5:Yb3+/Tm3+ based upconversion nanoparticles (UCNPs). This multifunctional DDS simultaneously possesses drug delivery and optical/magnetic/X-ray computed tomography imaging capabilities. The DOX can be selectively released by cleavage of hydrazone bonds in acidic environment, which shows a pH-triggered drug release behavior. The MTT assay shows these DOX-conjugated UCNPs exhibit obvious cytotoxic effect on HeLa cells. Moreover, to improve the upconversion luminescence intensity, core-shell structured UCNPs were constructed. The invitro upconversion luminescence images of these UCNPs uptaken by HeLa cells show bright emission with high contrast. In addition, these UCNPs were further explored for T1-weighted magnetic resonance (MR) and X-ray computed tomography (CT) imaging invitro. Long-term invivo toxicity studies indicated that mice intravenously injected with 10mg/kg of UCNPs survived for 40 days without any apparent adverse effects to their health. The results indicate that this multifunctional drug-delivery system with optimized size, excellent optical/MR/CT trimodal imaging capabilities, and pH-triggered drug release property is expected to be a promising platform for simultaneous cancer therapy and bioimaging. © 2013 Elsevier Ltd.


Liu Z.,CAS Changchun Institute of Applied Chemistry | Liu Z.,University of Chinese Academy of Sciences | Li Z.,CAS Changchun Institute of Applied Chemistry | Li Z.,University of Chinese Academy of Sciences | And 5 more authors.
Biomaterials | Year: 2012

Nanoparticulate imaging agents offer excellent diagnostic and therapeutic capabilities due to their intense and stable output, strong target binding via multiple ligands, as well as tunable biodistribution profiles. In the present work, we designed and synthesized PEGylated Yb 2O 3:Er nanoparticles with high Yb content in single particle (denoted as PEG-UCNPs) suitable for both X-ray CT imaging and up-conversion imaging. These PEG-UCNPs were facile to construct, possessed excellent stability against in vivo environment, and held long blood circulation time. Cell-cytotoxicity assay, hemolyticity, and post-injection histology analysis further demonstrated the excellent biocompatibility, indicating the feasibilities of PEG-UCNPs for in vivo applications. Compared with routinely used Iobitridol in clinic, well-prepared PEG-UCNPs provided much significantly enhanced contrast at a clinical 120 kVp voltage. By doping 5% Er 3+ into the nanoparticles, PEG-UCNPs presented a long-term stable and nearly single-band red up-conversion emission upon continuous irradiation with an assistant of a 980 laser. In addition, pharmacokinetics, biodistribution, as well as clearance of nanoparticles were studied after intravenous injection in a mouse model, reflecting their overall safety. PEG-UCNPs composed of intrinsic up-conversion luminescence property, higher X-ray absorption over Iobitridol, as well as excellent biocompatibility represented a nanoplatform for biomedicine applications. © 2012 Elsevier Ltd.


Guo H.,CAS Changchun Institute of Applied Chemistry | Zhu Y.,Lichtenbergstrasse 4 | Qiu S.,Jilin University | Lercher A.J.,Lichtenbergstrasse 4 | Zhang H.,CAS Changchun Institute of Applied Chemistry
Advanced Materials | Year: 2010

Strategies for synthesizing of nanoscale single or bimetallic lanthanide metal-organic framework (MOF) materials and their transformation into Eu 1-xTbx-MOF thin films are reported. The thin films prepared via spin coating deposition method are smooth, dense and mechanically stable. They also exhibit marked luminescent properties and efficient Tb 3+-to-Eu3+ energy transferability. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhao C.,Jilin University | Lin H.,Jilin University | Zhang Q.,CAS Changchun Institute of Applied Chemistry | Na H.,Jilin University
International Journal of Hydrogen Energy | Year: 2010

Sulfonated poly(arylene ether ketone) bearing carboxyl groups (SPAEK-C) membranes were first modified by alternating deposition of oppositely charged polyaniline (PANI) and phosphotungstic acid (PWA) via the layer-by-layer method in order to prevent the crossover of methanol in a direct methanol fuel cell. The methanol permeability of SPAEK-C-(PANI/PWA)5 is 2 orders of magnitude less than those of Nafion 117 and pristine SPAEK-C. Furthermore, the modified membrane shows a proton conductivity of 0.093 Scm-1 at 25 °C and 0.24 Scm-1 at 80 °C, which are superior to those of Nafion 117 and pristine SPAEK-C. Fourier transform infrared spectroscopy confirms that PANI and PWA are assembled in the multilayers. The SEM images show the presence of thin PANI/PWA layers coated on the SPAEK-C membrane. Thermal stability, water uptake, water swelling, proton and electron conductivity at different temperature of the SPAEK-C and SPAEK-C-(PANI/PWA)n membranes are also investigated. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.


Gao H.,CAS Changchun Institute of Applied Chemistry | Gao H.,Jilin University | Li Y.,Northeast Normal University | Zhou Y.-G.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Advanced Synthesis and Catalysis | Year: 2011

We present a highly active, inexpensive, universally applicable, and markedly stable [1,3-bis(diphenylphosphino)propane]nickel(II) chloride [Ni(dppp)Cl2] catalyst that is capable of effecting the Suzuki-Miyaura cross-coupling of the inherently less reactive but readily available aryl tosylates and mesylates with only 1amol% loading and in the absence of extra supporting ligand. Under the optimized reaction conditions, cross-coupling of a wide range of activated, non-activated, and deactivated, as well as sterically hindered and heteroaromatic substrates (36 examples) could proceed efficiently to afford the coupled products in 53-99% yields. Consequently, the results presented in this work provide a significant advance in Suzuki-Miyaura cross-coupling in terms of generality, practicality, and cost which are key concerns in recent research regarding transition metal-catalyzed cross-couplings. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Hu Y.,CAS Changchun Institute of Applied Chemistry | Hu Y.,Jilin University | Wang K.,CAS Changchun Institute of Applied Chemistry | Zhang Q.,CAS Changchun Institute of Applied Chemistry | And 4 more authors.
Biomaterials | Year: 2012

An efficient DNA impedance biosensing platform is constructed, in which positively charged N,N-bis-(1-aminopropyl-3-propylimidazol salt)-3,4,9,10-perylene tetracarboxylic acid diimide (PDI) is anchored to graphene sheets. The π-π stacking and electronic interactions are elucidated by the distinct absorption features in UV-vis spectra and by quenching perylene fluorescence in contact with graphene. The rational design and tailoring of graphene surface invest it with desired properties (dispersive, structural, photoelectrical and conductive, etc.) and boost its application. Electrostatic interaction between PDI's positively charged imidazole rings and negatively charged phosphate backbones of single-stranded DNA (ssDNA) facilitates ssDNA immobilization. This manner is different from these mainly based on the attraction between the rings in DNA bases and the hexagonal cells of graphene, which is disturbed after hybridization and causes the leaving of formed double-stranded DNA from graphene surface. The electrostatic ssDNA grafting occupies phosphate backbones and particularly leaves the bases available for efficient hybridization. DNA immobilization and hybridization lead to PDI/graphene interfacial property changes, which are monitored by electrochemical impedance spectroscopy and adopted as the analytical signal. The conserved sequence of the pol gene of human immunodeficiency virus 1 is satisfactorily detected via this PDI/graphene platform and shows high reproducibility, selectivity. © 2011 Elsevier Ltd.


Yu C.,CAS Changchun Institute of Applied Chemistry | Du H.,Jilin University | You T.,CAS Changchun Institute of Applied Chemistry
Talanta | Year: 2011

The tricyclic antidepressants (TCA) imipramine (Imi) and trimipramine (Tri) were successfully analyzed by capillary electrophoresis (CE) coupling with Tris(2,2-bipyridyl) ruthenium(II)-based (Ru(bpy) 3 2+) end-column electrochemiluminescence (ECL) detection. The addition of β-CD to the running buffer was found to enable baseline separation of the two analytes and the addition of acetonitrile (ACN) as an organic additive to improve the repeatability and sensitivity of the CE method. Under the optimized separation and detection conditions (50 mM PBS (pH = 7.0) and 2 mM Ru(bpy) 3 2+ in the ECL detection cell, 20 mM Tris (pH = 2.0), 0.2 mM β-CD and 20% ACN (v/v) as running buffer), wide linear ranges of 0.1-5 μM and 0.1-5 μM were achieved, with the correlation coefficients of 0.9990 (n = 8) and 0.9980 (n = 8) for Imi and Tri, respectively. Detection limits 5 nM and 1 nM (S/N = 3) were obtained for Imi and Tri, respectively. The method was also successfully applied for the determination of Imi in pharmaceutical dosage form. © 2010 Elsevier B.V. All rights reserved.


Wang Y.,CAS Changchun Institute of Applied Chemistry | Chu X.,Jilin University | Suo Z.,Ohio State University | Wang E.,CAS Changchun Institute of Applied Chemistry | And 3 more authors.
Journal of the American Chemical Society | Year: 2012

Approximately three-fourths of eukaryotic proteins are composed of multiple independently folded domains. However, much of our understanding is based on single domain proteins or isolated domains whose studies directly lead to well-known energy landscape theory in which proteins fold by navigating through a funneled energy landscape toward native structure ensembles. The degrees of freedom for proteins with multiple domains are many orders of magnitude larger than that for single domain proteins. Now, the question arises: How do the multidomain proteins solve the "protein folding problem"? Here, we specifically address this issue by exploring the structure folding relationship of Sulfolobus solfataricus DNA polymerase IV (DPO4), a prototype Y-family DNA polymerase which contains a polymerase core consisting of a palm (P domain), a finger (F domain), and a thumb domain (T domain) in addition to a little finger domain (LF domain). The theoretical results are in good agreement with the experimental data and lead to several theoretical predictions. Finally, we propose that for rapid folding into well-defined conformations which carry out the biological functions, four-domain DPO4 employs a divide-and-conquer strategy, that is, combining multiple individual folding funnels into a single funnel (domains fold independently and then coalesce). In this way, the degrees of freedom for multidomain proteins are polynomial rather than exponential, and the conformational search process can be reduced effectively from a large to a smaller time scale. © 2012 American Chemical Society.


Wang N.,CAS Changchun Institute of Applied Chemistry | Chen Z.,Jilin University | Wei W.,Jilin University | Jiang Z.,Jilin University
Journal of the American Chemical Society | Year: 2013

Thanks to their many favorable advantages, polymer solar cells exhibit great potential for next-generation clean energy sources. Herein, we have successfully designed and synthesized a series of new fluorinated benzothiadiazole-based conjugated copolymers PBDTTEH-DT HBTff (P1), PBDTTEH-DTEHBTff (P2), and PBDTHDO-DTHBTff (P3). The power conversion efficiencies of 4.46, 6.20, and 8.30% were achieved for P1-, P2-, and P3-based devices within ∼100 nm thickness active layers under AM 1.5G illumination without any processing additives or post-treatments, respectively. The PCE of 8.30% for P3 is the highest value for the reported traditional single-junction polymer solar cells via a simple fabrication architecture without any additives or post-treatments. In addition, it is noteworthy that P3 also allows making high efficient polymer solar cells with high PCEs of 7.27 and 6.56% under the same condition for ∼200 and ∼300 nm thickness active layers, respectively. Excellent photoelectric properties and good solubility make polymer P3 become an alternative material for high-performance polymer solar cells. © 2013 American Chemical Society.


Fan H.,Jilin University | Li H.,CAS Changchun Institute of Applied Chemistry | Liu B.,Jilin University | Lu Y.,Jilin University | And 2 more authors.
ACS Applied Materials and Interfaces | Year: 2012

A series of Bi 2O 3/BaTiO 3 composite photocatalysts with different mass ratios of Bi 2O 3 vs BaTiO 3 were prepared by an impregnating-annealing method. X-ray diffraction (XRD), high-resolution transmission electron microscopic (HRTEM), and UV-vis diffuse reflection spectroscopy (DRS) confirmed that Bi 2O 3 and BaTiO 3 coexisted in the composites. The results of surface photovoltage (SPV) experiments showed enhancements of photovoltaic response in composites, which indicated a higher separation efficiency of photoinduced charges due to the establishment of an efficient interfacial electric field between Bi 2O 3 and BaTiO 3 in the composites. The consistency of phtocatalytic activity and photovoltaic response intensity of photocatalysts showed that the efficiency interfacial electric field between Bi 2O 3 and BaTiO 3 played an important role in improving the degradation efficiency of Rhodamine B (RhB). The 60%-Bi 2O 3/BaTiO 3 sample with the best activity was found by optimizing the mass ratios of Bi 2O 3 vs. BaTiO 3. On the basis of the work function (WF) measurements, a reasonable energy band diagram was proposed for BaTiO 3/Bi 2O 3 composite. It would be helpful in designing and constructing high efficiency heterogeneous semiconductor photocatalyst. © 2012 American Chemical Society.


Jian Z.,CAS Changchun Institute of Applied Chemistry | Jian Z.,University of Chinese Academy of Sciences | Tang S.,Jilin University | Cui D.,CAS Changchun Institute of Applied Chemistry
Chemistry - A European Journal | Year: 2010

A novel linked-half-sandwich lutetium-bis(allyl) complex [(C 5Me 4-C 5H 4N) Lu(η 3-C 3H 5) 2] (1) attached by a pyridyl-functionalized cyclopentadienyl ligand was synthesized and fully characterized. Complex 1 in combination with [Ph 3C][B(C 6F 5) 4] exhibited unprecedented dual catalysis with outstanding activities in highly syndiotactic (rrrr>99 %) styrene polymerization and distinguished cis-1,4-selective (99 %) butadiene polymerization, respectively. Strikingly, this catalyst system exhibited remarkable activity (396 kg copolymer (mol Lu h) -1) for the copolymerization of butadiene and styrene. Irrespective of whether the monomers were fed in concurrent mode or sequential addition of butadiene followed by styrene, diblock copolymers were obtained exclusively, which was confirmed by a kinetics investigation of monomer conversion of copolymerization with time. In the copolymers, the styrene incorporation rate varied from 4.7 to 85.4 mol %, whereas the polybutadiene (PBD) block was highly cis-1,4-regulated (95 %) and the polystyrene segment remained purely syndiotactic (rrrr>99 %). Correspondingly, the copolymers exhibited glass transition temperatures (T g) around -107 °C and melting points (T m) around 268 °C; typical values for diblock microstructures. Such copolymers cannot be accessed by any other methods known to date. X-ray powder diffraction analysis of these diblock copolymers showed that the crystallizable syndiotactic polystyrene (syn-PS) block was in the toluene Î clathrate form. The AFM micrographs of diblock copolymer showed a remarkable phase-separation morphology of the cis-1,4-PBD block and syn-PS block. This represents the first example of a lutetium-based catalyst showing both high activity and selectivity for the (co)polymerization of styrene and butadiene. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhao L.,CAS Changchun Institute of Applied Chemistry | Zhao L.,Jilin University | Wu J.,CAS Changchun Institute of Applied Chemistry | Ke H.,CAS Changchun Institute of Applied Chemistry | Tang J.,CAS Changchun Institute of Applied Chemistry
Inorganic Chemistry | Year: 2014

Reactions of LnIII perchlorate (Ln = Gd, Tb, Dy, and Ho), NiCl2·6H2O, and a polydentate Schiff base resulted in the assembly of novel isostructural hexanuclear Ni4Ln2 complexes [Ln = Gd (1), Tb (2), Dy (3), Ho (4)] with an unprecedented 3d-4f metal topology consisting of two defect-dicubane units. The corresponding Ni4Y2 (5) complex containing diamagnetic YIII atoms was also isolated to assist the magnetic studies. Interestingly, complexes 2 and 3 exhibit SMM characteristics and 4 shows slow relaxation of the magnetization. The absence of frequency-dependent in-phase and out-of-phase signals for the Ni-Y species suggests that the Ln ions contribution to the slow relaxation must be effectual as previously observed in other Ni-Dy samples. However, the observation of ″ signals with zero dc field for the Ni-Tb and Ni-Ho derivatives is notable. Indeed, this is the first time that such a behavior is observed in the Ni-Tb and Ni-Ho complexes. © 2014 American Chemical Society.


Wang K.,Jilin University | Zhao F.,CAS Changchun Institute of Applied Chemistry | Wang C.,Jilin University | Chen S.,Jilin University | And 5 more authors.
Advanced Functional Materials | Year: 2013

Two coordination complex emitters as well as host materials Be(PPI) 2 and Zn(PPI)2 (PPI = 2-(1-phenyl-1H-phenanthro[9,10-d] imidazol-2-yl)phenol) are designed, synthesized, and characterized. The incorporation of the metal atom leads to a twisted conformation and rigid molecular structure, which improve the thermal stability of Be(PPI)2 and Zn(PPI)2 with high Td and Tg at around 475 and 217 °C, respectively. The introduction of the electron-donating phenol group results in the emission color shifting to the deep-blue region and the emission maximum appears at around 429 nm. This molecular design strategy ensures that the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) HOMO and LUMO of Be(PPI)2 and Zn(PPI) 2 localize on the different moieties of the molecules. Therefore, the two complexes have an ambipolar transport property and a small singlet-triplet splitting of 0.35 eV for Be(PPI)2 and 0.21 eV for Zn(PPI) 2. An undoped deep-blue fluorescent organic light-emitting device (OLED) that uses Be(PPI)2 as emitter exhibits a maximum power efficiency of 2.5 lm W-1 with the CIE coordinates of (0.15, 0.09), which are very close to the National Television Standards Committee (NTSC) blue standard (CIE: 0.14, 0.08). Green and red phosphorescent OLEDs (PhOLEDs) that use Be(PPI)2 and Zn(PPI)2 as host materials show high performance. Highest power efficiencies of 67.5 lm W-1 for green PhOLEDs and 21.7 lm W-1 for red PhOLEDs are achieved. In addition, the Be(PPI)2-based devices show low-efficiency roll-off behavior, which is attributed to the more balanced carrier-transport property of Be(PPI)2. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Tian M.,Jilin University | Jia Q.,Jilin University | Liao W.,CAS Changchun Institute of Applied Chemistry
Journal of Rare Earths | Year: 2013

Synergistic solvent extraction of rare earth elements (REEs) from nitrate medium was investigated with mixtures of 8-hydroxyquinoline (HQ) and acidic organophosphorus extractants, bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex 301) and bis(2,4,4-trimethylpentyl) monothiophosphinic acid (Cyanex 302). The extraction behavior of Cyanex 301/Cyanex 302 and their binary mixtures with HQ towards several lanthanoids (La, Nd, Sm, Tb, Ho, Tm) and yttrium (Y) was investigated. The separation ability of REEs was studied according to the various extraction effects. The extraction mechanisms for yttrium were studied with the methods of slope analysis and constant moles in the synergistic systems. The extracted compounds, the equilibrium constants, and thermodynamic functions were also determined.


Li W.,Jilin University | Liu D.,Jilin University | Shen F.,Jilin University | Ma D.,CAS Changchun Institute of Applied Chemistry | And 5 more authors.
Advanced Functional Materials | Year: 2012

In an organic electroluminescent (EL) device, the recombination of injected holes and electrons produces what appears to be an ion-pair or charge-transfer (CT) exciton, and this CT exciton decays to produce one photon directly, or relaxes to a low-lying local exciton (LE). Thus the full utilization of both the energy of the CT exciton and the LE should be a pathway for obtaining high-efficiency EL. Here, a twisting donor-acceptor (D-A) triphenylamine- imidazol molecule, TPA-PPI, is reported: its synthesis, photophysics, and EL performance. Prepared by a manageable, one-pot cyclizing reaction, TPA-PPI exhibits deep-blue emission with high quantum yields (90%) both in solution and in the solid state. Fluorescent solvatochromic experiments for TPA-PPI solutions show a red-shift of 57 nm (3032 cm -1) from low-polarity hexane (406 nm) to high-polarity acetonitrile (463 nm), accompanied by the gradual disappearance of the vibrational band in the spectra with increased solvent polarity. The photophysical investigation and DFT analysis suggest an intercrossed CT and LE excited state of the TPA-PPI, originating from its twisting D-A configuration. This is a rare instance that a CT-state material shows highly efficient deep-blue emission. EL characterization demonstrates that, as a deep-blue emitter with CIE coordinates of (0.15, 0.11), the performance of a TPA-PPI-based device is rather excellent, displaying a maximum current efficiency of >5.0 cd A -1, and a maximum external quantum efficiency of >5.0%, corresponding to a maximum internal quantum efficiency of >25%. The effective utilization of the excitation energy arising from materials with intercrossed-excited-state (LE and CT) characters is thought to be beneficial for the improved efficiency of EL devices. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang Y.,City University of Hong Kong | Kalytchuk S.,City University of Hong Kong | Zhang Y.,City University of Hong Kong | Zhang Y.,Jilin University | And 4 more authors.
Journal of Physical Chemistry Letters | Year: 2014

Multicolor luminescent materials are of immense importance nowadays, while it still constitutes a challenge to achieve luminescence color tunability, transparency, and flexibility at the same time. Here we show how ultrasmall carbon dots (CDs) fluorescing strongly across the visible spectrum can be surface functionalized and incorporated into highly flexible hybrid materials by combination with ionic liquids within silica gel networks to form CD-ionogels with properties promising for fabrication of flexible displays and other optical technologies without the use of any toxic materials. We demonstrate how the emission from such hybrid materials can be tuned across a large range of the Commission Internationale de lEnclairage (CIE) display gamut giving full-color performance. We highlight how the rich ladder of emissive states attributable to organic functional groups and CD surface functionalization supports a smooth sequential multiple self-absorption tuning mechanism to red shift continuously from blue emitting n-π* transitions down through the lower energy states. © 2014 American Chemical Society.


Yuan S.,CAS Changchun Institute of Applied Chemistry | Yuan S.,Jilin University | Huang X.-L.,CAS Changchun Institute of Applied Chemistry | Ma D.-L.,CAS Changchun Institute of Applied Chemistry | And 4 more authors.
Advanced Materials | Year: 2014

Arrays of aligned porous CuO nanorods are obtained by a facile and scalable method of engraving Cu foil in situ. Direct use of the arrays as a flexible and binder-free sodium-ion battery anode - without adding auxiliary materials - results in superior electrochemical performance, including cycle stability and rate capability, even at room temperature. This can be attributed to the unique array structure and the lack of binder in the electrode. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Chang Y.-F.,CAS Changchun Institute of Applied Chemistry | Chang Y.-F.,Northeast Normal University | Lu Z.-Y.,Jilin University | An L.-J.,CAS Changchun Institute of Applied Chemistry | Zhang J.-P.,Northeast Normal University
Journal of Physical Chemistry C | Year: 2012

The reorganization energy and the charge transfer integral between the initial and final states are two key parameters of charge transport. In this study, we find that the internal reorganization energies of molecules can be reduced effectively by cyanation on the tetracene molecule, which is helpful to improve the carrier mobilities of investigated molecules. On the basis of the polymorph predictor, the appreciated crystal structures of 5-cyanotetracene (1CT), 5,11-dicyanotetracene (2CT), and 5,6,11,12-tetracyanotetracene (4CT) with π-π stacking favorable to enhance the charge transfer integral were obtained. Benefiting from a low internal reorganization energy and dense packing structure, high hole motilities (6.0 and 6.2 cm 2 V -1 s -1 for 1CT-9 and 4CT-2, respectively) were achieved. Both 1CT-9 and 4CT-2 are promising candidates for high carrier mobility organic optoelectronic functional materials. The process that constructs crystal structures from single molecules provides a rational way for the search of high-performance organic photovoltaic materials. © 2011 American Chemical Society.


Tong J.,Jilin University | Tong J.,CAS Changchun Institute of Applied Chemistry | Li Y.,Jilin University | Wu D.,Jilin University | Wu Z.-J.,CAS Changchun Institute of Applied Chemistry
Inorganic Chemistry | Year: 2012

A new series of polynuclear superalkali cations YLi 3 + (Y = CO 3, SO 3, SO 4, O 4, and O 5) has been created when the central group is surrounded by alkali atoms. The structural characteristics and stabilities of these systems are provided on the basis of ab initio methods. In the lowest-energy structure of the CO 3Li 3 +, SO 3Li 3 +, and SO 4Li 3 + cations, the central Y (Y = CO 3, SO 3, and SO 4) group features a slight distortion. The global minima of O 4Li 3 + and O 5Li 3 + are of the forms O 2 -(Li +) 3O 2 - and O 2 -(Li +) 3O 3 -, respectively, both of which contain two monovalent ion units. The structural integrity of the central Y group and the arrangement of the lithium ligands are two influencing factors on the vertical electron affinities (EA vert) for the YLi 3 + species. The YLi 3 + cation, with its lithium ligands being distributed evenly or far from each other, tends to exhibit a low EA vert value, whereas a greater extent of cleavage of the central Y group leads to a higher EA vert value and even makes some species lose their superalkali nature. © 2012 American Chemical Society.


Li Z.-W.,Jilin University | Sun Z.-Y.,CAS Changchun Institute of Applied Chemistry | Lu Z.-Y.,Jilin University
Journal of Physical Chemistry B | Year: 2010

We develop a novel mesoscale simulation model in order to study the hierarchical self-assembly of soft disklike particles in dilute solutions. In suitable solvent conditions, the soft anisotropic disklike particles first self-assemble into one-dimensional flexible threads, in accord with experiments. Then, intriguingly, the threads reversibly pack into flexible hexagonal bundles by decreasing the solvent quality. Hierarchical self-assembly of this type may be important to provide a strategy to create bundle structures by bottom-up self-assembly with a single type of soft and flexible building block and mimic the bundles commonly found in biological structures. © 2010 American Chemical Society.


Hao Y.,CAS Shenyang Institute of Metal Research | Liu F.,CAS Shenyang Institute of Metal Research | Han E.-H.,CAS Shenyang Institute of Metal Research | Anjum S.,CAS Changchun Institute of Applied Chemistry | Xu G.,CAS Changchun Institute of Applied Chemistry
Corrosion Science | Year: 2013

Epoxy coatings containing different volume fractions of zinc phosphate have been successfully prepared and their inhibitive properties have been studied by electrochemical impedance spectroscopy (EIS) and immersion tests. The results show that zinc phosphate can improve the protection ability of epoxy coatings and its best volume fraction is 30%. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) results indicate that the presence of zinc phosphate can form an inhibiting film which is composed of the phosphating film of FePO4, Fe2O3, and FeO, as well as the shielding film of zinc phosphate on the steel surface. © 2012 Elsevier Ltd.


Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,Jilin University | Wang J.,State University of New York at Stony Brook
Advances in Physics | Year: 2015

We present a review of the recently developed landscape and flux theory for non-equilibrium dynamical systems. We point out that the global natures of the associated dynamics for non-equilibrium system are determined by two key factors: the underlying landscape and, importantly, a curl probability flux. The landscape (U) reflects the probability of states (P) () and provides a global characterization and a stability measure of the system. The curl flux term measures how much detailed balance is broken and is one of the two main driving forces for the non-equilibrium dynamics in addition to the landscape gradient. Equilibrium dynamics resembles electron motion in an electric field, while non-equilibrium dynamics resembles electron motion in both electric and magnetic fields. The landscape and flux theory has many interesting consequences including (1) the fact that irreversible kinetic paths do not necessarily pass through the landscape saddles; (2) non-equilibrium transition state theory at the new saddle on the optimal paths for small but finite fluctuations; (3) a generalized fluctuation-dissipation relationship for non-equilibrium dynamical systems where the response function is not just equal to the fluctuations at the steady state alone as in the equilibrium case but there is an additional contribution from the curl flux in maintaining the steady state; (4) non-equilibrium thermodynamics where the free energy change is not just equal to the entropy production alone, as in the equilibrium case, but also there is an additional house-keeping contribution from the non-zero curl flux in maintaining the steady state; (5) gauge theory and a geometrical connection where the flux is found to be the origin of the gauge field curvature and the topological phase in analogy to the Berry phase in quantum mechanics; (6) coupled landscapes where non-adiabaticity of multiple landscapes in non-equilibrium dynamics can be analyzed using the landscape and flux theory and an eddy current emerges from the non-zero curl flux; (7) stochastic spatial dynamics where landscape and flux theory can be generalized for non-equilibrium field theory. We provide concrete examples of biological systems to demonstrate the new insights from the landscape and flux theory. These include models of (1) the cell cycle where the landscape attracts the system down to an oscillation attractor while the flux drives the coherent motion on the oscillation ring, the different phases of the cell cycle are identified as local basins on the cycle path and biological checkpoints are identified as local barriers or transition states between the local basins on the cell-cycle path; (2) stem cell differentiation where the Waddington landscape for development as well as the differentiation and reprogramming paths can be quantified; (3) cancer biology where cancer can be described as a disease of having multiple cellular states and the cancer state as well as the normal state can be quantified as basins of attractions on the underlying landscape while the transitions between normal and cancer states can be quantified as the transitions between the two attractors; (4) evolution where more general evolution dynamics beyond Wright and Fisher can be quantified using the specific example of allele frequency-dependent selection; (5) ecology where the landscape and flux as well as the global stability of predator-prey, cooperation and competition are quantified; (6) neural networks where general asymmetrical connections are considered for learning and memory, gene self-regulators where non-adiabatic dynamics of gene expression can be described with the landscape and flux in expanded dimensions and analytically treated; (7) chaotic strange attractor where the flux is crucial for the chaotic dynamics; (8) development in space where spatial landscape can be used to describe the process and pattern formation. We also give the philosophical implications of the theory and the outlook for future studies. © 2015 Taylor & Francis.


Wang W.,Jilin University | Ma D.,CAS Changchun Institute of Applied Chemistry | Pan S.,Jilin University | Yang Y.,Jilin University
Applied Physics Letters | Year: 2012

In this letter, the hysteresis mechanism of organic thin-film transistors (OTFTs) with polyvinyl alcohol (PVA) as gate dielectric is studied. By examining OTFTs with a blocking polymer layer between gate and PVA or between channel and PVA, we confirm that the origin of the hysteresis is caused by the holes injected from the gate and/or from the channel and trapped in the interface of pentacene/PVA and the PVA bulk. A method is proposed to reduce the hysteresis. As a result, a pentacene OTFT with free-hysteresis and high mobility of 1.8 cm 2/Vs is achieved by a triple-layer polymer dielectric at low-operating voltages. © 2012 American Institute of Physics.


Wang J.,Northeast Normal University | Han D.,CAS Changchun Institute of Applied Chemistry | Wang X.,Northeast Normal University | Qi B.,Northeast Normal University | Zhao M.,Jilin University
Biosensors and Bioelectronics | Year: 2012

Polyoxometalates (H 3PW 12O 40, H 4SiW 12O 40 and H 3PMo 12O 40) have been proven to possess intrinsic peroxidase-like activity for the first time, which can catalyze oxidation of the peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) by H 2O 2 to form a blue color in aqueous solution. Among them, H 3PW 12O 40 (PW 12) exhibits higher catalytic activity to TMB than natural enzyme HRP and other two POMs. In addition, H 3PW 12O 40/graphene exhibited higher activity than H 3PW 12O 40 in this catalytic oxidation reaction due to the effect of graphene in promoting the electron transfer between the substrate and catalyst. POMs/H 2O 2/TMB system provides a simple, accurate approach to colorimetric detection for H 2O 2 or glucose. The colorimetric method based on POMs showed good response toward H 2O 2 and glucose detection with a linear range from 1.34×10 -7 to 6.7×10 -5mol/L and 1×10 -7 to 1×10 -4mol/L, respectively. The results showed that it is a simple, cheap, more convenient, highly selective, sensitive, and easy handling colorimetric assay. © 2012 Elsevier B.V.


Wang P.,CAS Changchun Institute of Applied Chemistry | Zhai Y.,CAS Changchun Institute of Applied Chemistry | Wang D.,Jilin University | Dong S.,CAS Changchun Institute of Applied Chemistry
Nanoscale | Year: 2011

The construction of reduced graphene oxide or graphene oxide with semiconductor has gained more and more attention due to its unexpected optoelectronic and electronic properties. The synthesis of reduced graphene oxide (RGO) or graphene oxide-semiconductor nanocomposite with well-dispersed decorated particles is still a challenge now. Herein, we demonstrate a facile method for the synthesis of graphene oxide-amorphous TiO2 and reduced graphene oxide-anatase TiO2 nanocomposites with well-dispersed particles. The as-synthesized samples were characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-Vis absorption spectroscopy, Fourier transform infrared spectrometry, and thermogravimetric analysis. The photovoltaic properties of RGO-anatase TiO 2 were also compared with that of similar sized anatase TiO 2 by transient photovoltage technique, and it was interesting to find that the combination of reduced graphene oxide with anatase TiO2 will significantly increase the photovoltaic response and retard the recombination of electron-hole pairs in the excited anatase TiO2. © 2011 The Royal Society of Chemistry.


Ai K.,CAS Changchun Institute of Applied Chemistry | Liu Y.,CAS Changchun Institute of Applied Chemistry | Liu J.,Jilin University | Yuan Q.,Jilin University | And 2 more authors.
Advanced Materials | Year: 2011

X-ray computed tomography (CT) is regarded as one of most powerful diagnostic imaging techniques. [1] With deep tissue penetration and high resolution, it is capable of providing 3D images of the entire body with exquisite contrast. Currently, the only CT contrast agents approved for clinical use are small iodinated molecules. [2a] These small iodinated molecules are routinely used as CT contrast agents in vivo with an emphasis on their cost-effectiveness rather than performance. To provide adequate contrast, it is typically necessary to use large doses of small iodinated molecules, which may lead to adverse effects in patients. [2b,c] Moreover, these molecules are cleared rapidly by the kidneys, within seconds to a few minutes. This short circulation time limits their applications to target imaging and angiography. Recently, nanomaterials have moved into the spotlight as imaging probes due to their unique optical and magnetic properties. In particular, the nanoparticles that comprise metal elements with high atomic number (high- Z ) for CT imaging are being explored with considerable interest for CT imaging. Compared to small iodinated molecules, these nanoparticles have the long circulation times, high contrast densities, and a functional surface; thus they are well-suited for in vivo angiography or target detection. [2a,3-5] Furthermore, the higher X-ray attenuation coefficient of these metal-based nanoparticles can confer higher efficacy than that of iodine-based contrast agents, including small iodinated molecules and iodine-based nanoparticles. Finally, these metal-based nanoparticles do not induce an iodine hypersensitivity reaction. [5]. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang M.,University of Rochester | Wang H.,University of Rochester | Tian H.,CAS Changchun Institute of Applied Chemistry | Geng Y.,CAS Changchun Institute of Applied Chemistry | Tang C.W.,University of Rochester
Advanced Materials | Year: 2011

High-efficiency organic photovoltaic (OPV) cells are mostly based on a bulk heterojunction [1] (BHJ) structure, which is essentially a thin film of mixed electron donor and acceptor. With few exceptions, the acceptor component is a fullerene-based material such as C 60 [2] and PCBM, [3] whereas a large variety of materials has been found to be useful as the donor component. [4] In order to achieve high power conversion efficiency, the donor-acceptor composition of the BHJ needs to be optimized with respect to light absorption and charge generation, including for instance the use of a low bandgap donor, [5] to complement the absorption of the acceptor and selecting a donor with proper highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels to match that of the acceptor. In this work, we show that it is possible to achieve a large open-circuit voltage ( V oc > 1.0 V) in a fullerene-based OPV with almost any donor, provided that the donor is present in a small concentration and that MoO x is used as the Schottky barrier contact [6] to the BHJ. With fine tuning of the donor concentration to overcome the hole-transport limitation in the BHJ, high power conversion efficiency (η PCE > 5%) has been realized. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang H.-G.,CAS Changchun Institute of Applied Chemistry | Ma D.-L.,CAS Changchun Institute of Applied Chemistry | Ma D.-L.,Jilin University | Huang Y.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Chemistry - A European Journal | Year: 2012

Porous V 2O 5 nanotubes, hierarchical V 2O 5 nanofibers, and single-crystalline V 2O 5 nanobelts were controllably synthesized by using a simple electrospinning technique and subsequent annealing. The mechanism for the formation of these controllable structures was investigated. When tested as the cathode materials in lithium-ion batteries (LIBs), the as-formed V 2O 5 nanostructures exhibited a highly reversible capacity, excellent cycling performance, and good rate capacity. In particular, the porous V 2O 5 nanotubes provided short distances for Li +-ion diffusion and large electrode-electrolyte contact areas for high Li +-ion flux across the interface; Moreover, these nanotubes delivered a high power density of 40.2 kW kg -1 whilst the energy density remained as high as 201 W h kg -1, which, as one of the highest values measured on V 2O 5-based cathode materials, could bridge the performance gap between batteries and supercapacitors. Moreover, to the best of our knowledge, this is the first preparation of single-crystalline V 2O 5 nanobelts by using electrospinning techniques. Interestingly, the beneficial crystal orientation provided improved cycling stability for lithium intercalation. These results demonstrate that further improvement or optimization of electrochemical performance in transition-metal-oxide-based electrode materials could be realized by the design of 1D nanostructures with unique morphologies. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li C.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Cell cycles, essential for biological function, have been investigated extensively. However, enabling a global understanding and defining a physical quantification of the stability and function of the cell cycle remains challenging. Based upon a mammalian cell cycle gene network, we uncovered the underlying Mexican hat landscape of the cell cycle. We found the emergence of three local basins of attraction and two major potential barriers along the cell cycle trajectory. The three local basins of attraction characterize the G1, S/G2, and M phases. The barriers characterize the G1 and S/G2 checkpoints, respectively, of the cell cycle, thus providing an explanation of the checkpoint mechanism for the cell cycle from the physical perspective. We found that the progression of a cell cycle is determined by two driving forces: curl flux for acceleration and potential barriers for deceleration along the cycle path. Therefore, the cell cycle can be promoted (suppressed), either by enhancing (suppressing) the flux (representing the energy input) or by lowering (increasing) the barrier along the cell cycle path. We found that both the entropy production rate and energy per cell cycle increase as the growth factor increases. This reflects that cell growth and division are driven by energy or nutrition supply. More energy input increases flux and decreases barrier along the cell cycle path, leading to faster oscillations. We also identified certain key genes and regulations for stability and progression of the cell cycle. Some of these findings were evidenced from experiments whereas others lead to predictions and potential anticancer strategies.


Liu J.,Xiangtan University | Zhou Y.,Xiangtan University | Wang J.,Xiangtan University | Pan Y.,Xiangtan University | And 2 more authors.
Chemical Communications | Year: 2011

Uniform yolk-shell V 2O 5 microspheres were synthesized via a facile template-free solvothermal route and subsequent calcination treatment in air. The resulting cathode materials showed a high specific capacity of 220 mA h g -1 after 30 cycles and good rate capability. © 2011 The Royal Society of Chemistry.


Hong W.,CAS Changchun Institute of Applied Chemistry | Hong W.,University of Chinese Academy of Sciences | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook | And 2 more authors.
Small | Year: 2014

The high-yield synthesis of dendritic Au/Pt and Au/PtCu nanowires is achieved through an effective heterogeneous, epitaxial growth strategy conducted in the water-phase to grow dendritic Pt and PtCu nanoshells on Au nanowires. The synthesized products exhibit excellent electrocatalytic activity towards methanol electrooxidation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Hong W.,CAS Changchun Institute of Applied Chemistry | Hong W.,University of Chinese Academy of Sciences | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,University of Chinese Academy of Sciences | And 3 more authors.
ACS Applied Materials and Interfaces | Year: 2014

In recent years, direct ethanol fuel cells (DEFCs) are attracting increasing attention owing to their wide applications. However, a significant challenge in the development of DEFC technology is the urgent need for highly active anode catalysts for the ethanol oxidation reaction. In this work, a facile and reproducible method for the high-yield synthesis of PdAu nanowire networks is demonstrated. The whole synthetic process is very simple, just mixing Na2PdCl4, HAuCl4, and KBr in an aqueous solution and using polyvinylpyrrolidone as a protective reagent while sodium borohydride as a reductant. The whole synthetic process can be simply performed at room temperature and completed in 30 min, which can greatly simplify the synthetic process and lower the preparation cost. Electrochemical catalytic measurement results prove that the as-prepared catalysts exhibit dramatically enhanced electrocatalytic activity for ethanol electrooxidation in alkaline solution. The facile synthetic process and excellent catalytic performance of the as-prepared catalysts demonstrate that they can be used as a promising catalyst for DEFCs. © 2014 American Chemical Society.


Wei G.,Friedrich - Schiller University of Jena | Xu F.,CAS Changchun Institute of Applied Chemistry | Li Z.,CAS Changchun Institute of Applied Chemistry | Jandt K.D.,Friedrich - Schiller University of Jena
Journal of Physical Chemistry C | Year: 2011

A facile and effective strategy to create carbon nanotube (CNT)-based platinum nanoparticle (PtNP) nanohybrids is reported in this work. First, we prepared toluene-soluble CNTs by modifying CNTs with a bifunctional linker, Z-glycine N-succinimidyl ester (Z-Gly-OSu), and then we synthesized superwater-soluble CNT-hemoglobin (HGB) hybrid nanofibers (about 5 mg/mL) by phase-transferring the Z-Gly-OSu-modified CNTs from toluene to HGB aqueous solution. The prepared CNT-HGB nanofibers were used as templates to bind PtCl6 2- ions by electrostatic interaction between proteins and negatively charged ions. CNT-PtNP nanohybrids were successfully synthesized by chemically reducing the PtCl6 2- ions with NaBH 4. The results indicate that PtNPs with uniform size and shape were created on the side wall of CNTs with high dispersion, and the loading of PtNPs on CNTs was improved with the increase of protein concentration used for the preparation of CNT-HGB nanofibers. A nonenzymatic amperometric sensor for highly sensitive and selective detection of glucose was successfully fabricated as demonstrating based on the synthesized CNT-PtNP nanohybrids. Under optimal conditions, selective detection of glucose in a linear concentration range of 28.0 μM-46.6 mM (R = 0.996) was obtained, which reveals a lower limit of detection and wider linear response compared to some previously reported glucose sensors. © 2011 American Chemical Society.


Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,Jiangnan University | Qin Y.-L.,CAS Changchun Institute of Applied Chemistry | Liu X.,Jiangnan University | Zhang X.-B.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

Graphene supported Pd@Co core-shell nanocatalysts with magnetically recyclability were synthesized via the in situ synthesis strategy utilizing the distinction in reduction potentials of the two precursors with appropriate reductant. The as-synthesized catalysts exerted satisfied catalytic activity (916 L mol -1 min -1) and recycle stability for hydrolytic dehydrogenation of ammonia borane. © 2012 The Royal Society of Chemistry.


Feng H.,State University of New York at Stony Brook | Han B.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Journal of Physical Chemistry B | Year: 2011

We explore the stochastic dynamics of self-regulative genes from fluctuations of molecular numbers and of on and off switching of gene states due to regulatory protein binding/unbinding to the genes. We found when the binding/unbinding is relatively fast (slow) compared with the synthesis/degradation of proteins in adiabatic (nonadiabatic) case the self-regulators can exhibit one or two peak (two peak) distributions in protein concentrations. This phenomena can also be quantified through Fano factors. This shows that even with the same architecture (topology of wiring) networks can have quite different functions (phenotypes), consistent with recent single molecule single gene experiments. We further found the inhibition and activation curves to be consistent with previous results (monomer binding) in adiabatic regime, but, in nonadiabatic regimes, show significantly different behaviors with previous predictions (monomer binding). Such difference is due to the slow (nonadiabatic) dimer binding/unbinding effect, and it has never been reported before. We derived the nonequilibrium phase diagrams of monostability and bistability in adiabatic and nonadiabatic regimes. We studied the dynamical trajectories of the self-regulating genes on the underlying landscapes from nonadiabatic to adiabatic limit, and we provide a global picture of understanding and show an analogy to the electron transfer problem. We studied the stability and robustness of the systems through mean first passage time (MFPT) from one peak (basin of attraction) to another and found both monotonic and nonmonotonic turnover behavior from adiabatic to nonadiabatic regimes. For the first time, we explore global dissipation by entropy production and the relation with binding/unbinding processes. Our theoretical predictions for steady state peaks, fano factos, inhibition/activation curves, and MFPT can be probed and tested from experiments. © 2010 American Chemical Society.


Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook | Zhang K.,CAS Changchun Institute of Applied Chemistry | Wang E.,CAS Changchun Institute of Applied Chemistry
Journal of Chemical Physics | Year: 2010

We developed a general framework to quantify three key ingredients for dynamics of nonequilibrium systems through path integrals in length space. First, we identify dominant kinetic paths as the ones with optimal weights, leading to effective reduction of dimensionality or degrees of freedom from exponential to polynomial so large systems can be treated. Second, we uncover the underlying nonequilibrium potential landscapes from the explorations of the state space through kinetic paths. We apply our framework to a specific example of nonequilibrium network system: lambda phage genetic switch. Two distinct basins of attractions emerge. The dominant kinetic paths from one basin to another are irreversible and do not follow the usual steepest descent or gradient path along the landscape. It reflects the fact that the dynamics of nonequilibrium systems is not just determined by potential gradient but also the residual curl flux force, suggesting experiments to test theoretical predictions. Third, we have calculated dynamic transition time scales from one basin to another critical for stability of the system through instantons. Theoretical predictions are in good agreements with wild type and mutant experiments. We further uncover the correlations between the kinetic transition time scales and the underlying landscape topography: the barrier heights along the dominant paths. We found that both the dominant paths and the landscape are relatively robust against the influences of external environmental perturbations and the system tends to dissipate less with less fluctuations. Our general framework can be applied to other nonequilibrium systems. © 2010 American Institute of Physics.


Zhang Y.,Japan International Center for Materials Nanoarchitectonics | Mori T.,Japan International Center for Materials Nanoarchitectonics | Niu L.,CAS Changchun Institute of Applied Chemistry | Ye J.,Japan International Center for Materials Nanoarchitectonics
Energy and Environmental Science | Year: 2011

By union of graphitic carbon nitride polymer with reduced graphene oxide (rGO, ≤1 wt%) via π-π stacking interaction, the band structure of carbon nitride could be well modulated. As a result, a significant increase of photocurrent was observed (e.g., when biased at 0.4 V vs. Ag/AgCl, the anodic photocurrent became 300% higher after doping). Not merely interesting in itself, graphene was also used as a general dopant for semiconductors in band-structure engineering. © 2011 The Royal Society of Chemistry.


Feng H.,State University of New York at Stony Brook | Han B.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Biophysical Journal | Year: 2012

We quantify the potential landscape to determine the global stability and coherence of biological oscillations. We explore a gene network motif in our experimental synthetic biology studies of two genes that mutually repress and activate each other with self-activation and self-repression. We find that in addition to intrinsic molecular number fluctuations, there is another type of fluctuation crucial for biological function: the fluctuation due to the slow binding/unbinding of protein regulators to gene promoters. We find that coherent limit cycle oscillations emerge in two regimes: an adiabatic regime with fast binding/unbinding and a nonadiabatic regime with slow binding/unbinding relative to protein synthesis/degradation. This leads to two mechanisms of producing the stable oscillations: the effective interactions from averaging the gene states in the adiabatic regime; and the time delays due to slow binding/unbinding to promoters in the nonadiabatic regime, which can be tested by forthcoming experiments. In both regimes, the landscape has a topological shape of the Mexican hat in protein concentrations that quantitatively determines the global stability of limit cycle dynamics. The oscillation coherence is shown to be correlated with the shape of the Mexican hat characterized by the height from the oscillation ring to the central top. The oscillation period can be tuned in a wide range by changing the binding/unbinding rate without changing the amplitude much, which is important for the functionality of a biological clock. A negative feedback loop with time delays due to slow binding/unbinding can also generate oscillations. Although positive feedback is not necessary for generating oscillations, it can make the oscillations more robust. © 2012 Biophysical Society.


Xie Z.,CAS Changchun Institute of Applied Chemistry | Xie Z.,Jiangxi University of Science and Technology | Liu Q.,CAS Changchun Institute of Applied Chemistry | Chang Z.,CAS Changchun Institute of Applied Chemistry | Zhang X.,CAS Changchun Institute of Applied Chemistry
Electrochimica Acta | Year: 2013

Zinc-cerium redox flow batteries (ZCBs) are emerging as a very promising new technology with the potential to store a large amount of energy economically and efficiently, thanking to its highest thermodynamic open-circuit cell voltage among all the currently studied aqueous redox flow batteries. However, there are numerous scientific and technical challenges that must be overcome if this alluring promise is to turn into reality, from designing the battery structure, to optimizing the electrolyte compositions and elucidating the complex chemical reactions that occur during charge and discharge. This review article is the first summary of the most significant developments and challenges of cerium half-cell and the current understanding of their chemistry. We are certain that this review will be of great interest to audience over a broad range, especially in fields of energy storage, electrochemistry, and chemical engineering. © 2012 Elsevier Ltd.


Li C.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
PLoS Computational Biology | Year: 2013

Cellular reprogramming has been recently intensively studied experimentally. We developed a global potential landscape and kinetic path framework to explore a human stem cell developmental network composed of 52 genes. We uncovered the underlying landscape for the stem cell network with two basins of attractions representing stem and differentiated cell states, quantified and exhibited the high dimensional biological paths for the differentiation and reprogramming process, connecting the stem cell state and differentiated cell state. Both the landscape and non-equilibrium curl flux determine the dynamics of cell differentiation jointly. Flux leads the kinetic paths to be deviated from the steepest descent gradient path, and the corresponding differentiation and reprogramming paths are irreversible. Quantification of paths allows us to find out how the differentiation and reprogramming occur and which important states they go through. We show the developmental process proceeds as moving from the stem cell basin of attraction to the differentiation basin of attraction. The landscape topography characterized by the barrier heights and transition rates quantitatively determine the global stability and kinetic speed of cell fate decision process for development. Through the global sensitivity analysis, we provided some specific predictions for the effects of key genes and regulation connections on the cellular differentiation or reprogramming process. Key links from sensitivity analysis and biological paths can be used to guide the differentiation designs or reprogramming tactics. © 2013 Li, Wang.


Li C.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Journal of the Royal Society Interface | Year: 2013

Cellular differentiation, reprogramming and transdifferentiation are determined by underlying gene regulatory networks. Non-adiabatic regulation via slow binding/unbinding to the gene can be important in these cell fate decisionmaking processes. Based on a stem cell core gene network, we uncovered the stem cell developmental landscape. As the binding/unbinding speed decreases, the landscape topography changes from bistable attractors of stem and differentiated states to more attractors of stem and other different cell states as well as substates. Non-adiabaticity leads to more differentiated cell types and provides a natural explanation for the heterogeneity observed in the experiments. We quantified Waddington landscapes with two possible cell fate decision mechanisms by changing the regulation strength or regulation timescale (nonadiabaticity). Transition rates correlate with landscape topography through barrier heights between different states and quantitatively determine global stability. We found the optimal speeds of these cell fate decision-making processes. We quantified biological paths and predict that differentiation and reprogramming go through an intermediate state (IM1), whereas transdifferentiation goes through another intermediate state (IM2). Some predictions are confirmed by recent experimental studies. © 2013 The Author(s) Published by the Royal Society.


Yan Z.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook
Proteins: Structure, Function and Bioinformatics | Year: 2015

Solvation effect is an important factor for protein-ligand binding in aqueous water. Previous scoring function of protein-ligand interactions rarely incorporates the solvation model into the quantification of protein-ligand interactions, mainly due to the immense computational cost, especially in the structure-based virtual screening, and nontransferable application of independently optimized atomic solvation parameters. In order to overcome these barriers, we effectively combine knowledge-based atom-pair potentials and the atomic solvation energy of charge-independent implicit solvent model in the optimization of binding affinity and specificity. The resulting scoring functions with optimized atomic solvation parameters is named as specificity and affinity with solvation effect (SPA-SE). The performance of SPA-SE is evaluated and compared to 20 other scoring functions, as well as SPA. The comparative results show that SPA-SE outperforms all other scoring functions in binding affinity prediction and "native" pose identification. Our optimization validates that solvation effect is an important regulator to the stability and specificity of protein-ligand binding. The development strategy of SPA-SE sets an example for other scoring function to account for the solvation effect in biomolecular recognitions. © 2015 Wiley Periodicals, Inc.


Zheng X.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook
PLoS Computational Biology | Year: 2015

We uncovered the universal statistical laws for the biomolecular recognition/binding process. We quantified the statistical energy landscapes for binding, from which we can characterize the distributions of the binding free energy (affinity), the equilibrium constants, the kinetics and the specificity by exploring the different ligands binding with a particular receptor. The results of the analytical studies are confirmed by the microscopic flexible docking simulations. The distribution of binding affinity is Gaussian around the mean and becomes exponential near the tail. The equilibrium constants of the binding follow a log-normal distribution around the mean and a power law distribution in the tail. The intrinsic specificity for biomolecular recognition measures the degree of discrimination of native versus non-native binding and the optimization of which becomes the maximization of the ratio of the free energy gap between the native state and the average of non-native states versus the roughness measured by the variance of the free energy landscape around its mean. The intrinsic specificity obeys a Gaussian distribution near the mean and an exponential distribution near the tail. Furthermore, the kinetics of binding follows a log-normal distribution near the mean and a power law distribution at the tail. Our study provides new insights into the statistical nature of thermodynamics, kinetics and function from different ligands binding with a specific receptor or equivalently specific ligand binding with different receptors. The elucidation of distributions of the kinetics and free energy has guiding roles in studying biomolecular recognition and function through small-molecule evolution and chemical genetics. © 2015 Zheng, Wang.


Li Y.,CAS Changchun Institute of Applied Chemistry | An L.,CAS Changchun Institute of Applied Chemistry | Huang Q.,Rutgers University
Journal of Physical Chemistry B | Year: 2014

Replica exchange Monte Carlo simulation equipped with an orientation-enhanced hydrophobic interaction was utilized to study the impacts of molar ratio and ionic strength on the complex formation of human serum albumin (HSA) and catechin. Only a small amount of catechins was found to act as bridges in the formation of HSA-catechin complexes. Selective binding behavior was observed at low catechin to HSA molar ratio (R). Increase of catechin amount can suppress HSA self-aggregation and diminish the selectivity of protein binding sites. Strong saturation binding with short-range interactions was found to level off at around 4.6 catechins per HSA on average, while this number slowly increased with R when long-range interactions were taken into account. Meanwhile, among the three rings of catechin, the 3, 4-dihydroxyphenyl (B-ring) shows the strongest preference to bind HSA. Neither the aggregation nor the binding sites of the HSA-catechin complex was sensitive to ionic strength, suggesting that the electrostatic interaction is not a dominant force in such complexes. These results provide a further molecular level understanding of protein-polyphenol binding, and the strategy employed in this work shows a way to bridge phase behaviors at macroscale and the distribution of binding sites at residue level. © 2014 American Chemical Society.


Zhou M.,CAS Changchun Institute of Applied Chemistry | Zheng X.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook | Dong S.,CAS Changchun Institute of Applied Chemistry
Bioinformatics | Year: 2011

Motivation: Biofuel cells (BFCs) based on enzymes and microbes are the promising future alternative sources of sustainable electrical energy under mild conditions (i.e. ambient temperature and neutral pH). By combining the adaptive behavior of BFCs self-regulating energy release with the versatility of biocomputing, we construct a novel gas-controlled biocomputing security system, which could be used as the potential implantable self-powered and 'smart' medical system with the logic diagnosis aim. Results: We have demonstrated a biocomputing security system based on BFCs. Due to the unique 'RESET' reagent of N2 applied in this work, the prepared biocomputing security system can be reset and cycled for a large number of times with no 'RESET' reagentbased 'waste'. This would be advantageous for the potential practical applications of such keypad lock as well as the development of biocomputing security devices. In order to validate the universality of the system and also to harvest energy directly from biofuels with enhanced power output, we replace the glucose with orange juice as the biofuel to operate BFCs-based biocomputing system, which also possesses the function of keypad lock. In addition, by introducing BFCs into the biocomputing security system, the adaptive behavior of the BFCs self-regulating the power release would be an immense advantage of such security keypad lock devices in potential self-powered implantable medical systems. The designed sequence gives the maximum power output and discriminate itself from the rest of the sequences. From this, we find that maximizing the dimensionless ratio of gap versus SD of the power output spectrum (a funnel in power outputs) gives the quantitative optimal design criterion. Therefore, our construction here may also provide a practical example and microscopic structural basis for mimicking the real biological network systems and bridge the gaps between the theoretical concepts and experiments important for biomolecular systems and synthetic biology. © The Author 2010. Published by Oxford University Press. All rights reserved.


Li C.,State University of New York at Stony Brook | Wang J.,State University of New York at Stony Brook | Wang J.,CAS Changchun Institute of Applied Chemistry
Cancer Research | Year: 2015

Cancer presents a serious threat to human health. The understanding of the cell fate determination during development and tumor-genesis remains challenging in current cancer biology. It was suggested that cancer stem cell (CSC) may arise from normal stem cells orbe transformed from normal differentiated cells. This gives hints on the connection between cancer and development. However, the molecular mechanisms of these cell-type transitions and the CSC formation remain elusive. We quantified landscape, dominant paths, and switching rates between cell types from a core gene regulatory network for cancer and development. Stem cell, CSC, cancer, and normal cell types emerge as basins of attraction on associated landscape. The dominant paths quantify the transition processes among CSC, stem cell, normal cell, and cancer cell attractors. Transition actions of the dominant paths are shown to be closely related to switching rates between cell types, but not always to the barriers in between, because of the presence of the curl flux. During the process of P53 gene activation, landscape topography changes gradually from a CSC attractor to a normal cell attractor. This confirms the roles of P53 of preventing the formation of CSC through suppressing self-renewal and inducing differentiation. By global sensitivity analysis according to landscape topography and action, we identified key regulations determining cell-type switchings and suggested testable predictions. From landscape view, the emergence of the CSCs and the associated switching to other cell types are the results of underlying interactions among cancer and developmental marker genes. This indicates that the cancer and development are intimately connected. This landscape and flux theoretical framework provides a quantitative way to understand the underlying mechanisms of CSC formation and interplay between cancer and development. © 2015 American Association for Cancer Research.


Ren J.,CAS Changchun Institute of Applied Chemistry | Ren J.,University of Chinese Academy of Sciences | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook | Wang E.,CAS Changchun Institute of Applied Chemistry
Chemistry - A European Journal | Year: 2013

At the gate: Colorimetric enantiorecognition of one oligopeptide was realized by virtue of a D-enantiomer specific DNA aptamer as chiral selector and unmodified gold nanoparticles as indicator. Oligopeptide enantiomers as inputs were introduced into colorimetric logic gates, which have the potential for enantiorecognition of oligopeptides (see figure). This system may lead to a better understanding of chiral recognition for information processing in natural systems. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang J.,CAS Changchun Institute of Applied Chemistry | Wang J.,State University of New York at Stony Brook | Xu L.,CAS Changchun Institute of Applied Chemistry | Wang E.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Biophysical Journal | Year: 2010

Differentiation from a multipotent stem or progenitor state to a mature cell is an essentially irreversible process. The associated changes in gene expression patterns exhibit time-directionality. This "arrow of time" in the collective change of gene expression across multiple stable gene expression patterns (attractors) is not explained by the regulated activation, the suppression of individual genes which are bidirectional molecular processes, or by the standard dynamical models of the underlying gene circuit which only account for local stability of attractors. To capture the global dynamics of this nonequilibrium system and gain insight in the time-asymmetry of state transitions, we computed the quasipotential landscape of the stochastic dynamics of a canonical gene circuit that governs branching cell fate commitment. The potential landscape reveals the global dynamics and permits the calculation of potential barriers between cell phenotypes imposed by the circuit architecture. The generic asymmetry of barrier heights indicates that the transition from the uncommitted multipotent state to differentiated states is inherently unidirectional. The model agrees with observations and predicts the extreme conditions for reprogramming cells back to the undifferentiated state. © 2010 by the Biophysical Society.


Zhang Y.,Hiroshima University | Wang X.,CAS Changchun Institute of Applied Chemistry | Zeng L.,Hiroshima University | Song S.,CAS Changchun Institute of Applied Chemistry | Liu D.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2012

A low-cost, fast, facile, green method, namely an ultrasound assisted approach, has been developed for the controlled synthesis of Cu 2O-graphene hybrid nanomaterials. By the protection of graphene nanosheets, the as-obtained anode material exhibited enhanced lithium ion battery performance. © 2012 The Royal Society of Chemistry.


Qin C.,Hong Kong Baptist University | Wong W.-Y.,Hong Kong Baptist University | Wang L.,CAS Changchun Institute of Applied Chemistry
Macromolecules | Year: 2011

A water-soluble organometallic conjugated polyelectrolyte P1 and its corresponding model complex M1 based on an aspartic acid-substituted fluorene spacer are reported, which possess good water solubility as well as intriguing fluorescent and phosphorescent dual-emissive properties in a completely organic-free aqueous medium at room temperature. A new colorimetric silver ion sensor based on P1 is developed, which shows high selectivity and sensitivity for Ag+ ions in buffered water solution because of the Ag +-induced intersystem crossing from the singlet to triplet states. The obvious color change from colorless to yellow upon exposure to Ag + ion is visible to the naked eyes and can be quantified colorimetrically by the visible absorption spectroscopic method. On the basis of the fluorescence intensity of P1 obtained in the fluorescence titration curves, a linear relationship is observed in the Stern-Volmer plot at low concentrations (1-5μM), and the corresponding Stern-Volmer quenching constant (KSV) of 1.9 × 105 M-1 for P1 is comparable to that obtained from the fluorescence titration studies. As determined by the Benesi-Hildebrand plot obtained from the absorption spectra, a 1:1 complex formation is anticipated between the Pt compound and Ag+ ion. The limit of detection is low at 0.5 μM, i.e., at concentrations in the ppb range. The present study represents an original approach using a water-soluble organometallic conjugated polyelectrolyte for the accurate and rapid detection of trace amounts of Ag+ ion in pure water. It also establishes a new system featuring dual-emissive properties of platinum(II) acetylide-based conjugated polymers for chemosensing application. © 2010 American Chemical Society.


Lin Y.,CAS Changchun Institute of Applied Chemistry | Zhang F.,Shanghai Normal University | Pan D.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

A series of (ZnS) x(CuInS 2) 1-x hierarchical micro/nano-structured solid solutions with precisely controlled chemical composition were synthesized via a facile one-pot solvothermal method. ZnO, Cu 2O, and In(OH) 3 are used as the starting materials and dissolved in ethanol dithiocarbamic acid which is formed from CS 2 and ethanolamine in situ. The ethanol dithiocarbamic acid not only serves as a thermally-degradable ligand, but also acts as sulfur source during synthesis, and can be completely removed by a simple calcination process. As-prepared (ZnS) x(CuInS 2) 1-x microspheres have a hierarchical micro/nano structure composed of around 7 nm nanoparticles. These samples show excellent photocatalytic H 2 evolution activity under visible-light irradiation without any noble metal loading owing to their high surface area (as high as 101.6 m 2 g -1) and unique hierarchical structure. © 2012 The Royal Society of Chemistry.


Han L.,University of Waterloo | Dong S.,CAS Changchun Institute of Applied Chemistry | Wang E.,CAS Changchun Institute of Applied Chemistry
Advanced Materials | Year: 2016

Increasing energy demands and environment awareness have promoted extensive research on the development of alternative energy conversion and storage technologies with high efficiency and environmental friendliness. Among them, water splitting is very appealing, and is receiving more and more attention. The critical challenge of this renewable-energy technology is to expedite the oxygen evolution reaction (OER) because of its slow kinetics and large overpotential. Therefore, developing efficient electrocatalysts with high catalytic activities is of great importance for high-performance water splitting. In the past few years, much effort has been devoted to the development of alternative OER electrocatalysts based on transition-metal elements that are low-cost, highly efficient, and have excellent stability. Here, recent progress on the design, synthesis, and application of OER electrocatalysts based on transition-metal elements, including Co, Ni, and Fe, is summarized, and some invigorating perspectives on the future developments are provided. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Choi W.H.,Hong Kong Baptist University | Tam H.L.,Hong Kong Baptist University | Ma D.,CAS Changchun Institute of Applied Chemistry | Zhu F.,Hong Kong Baptist University
Optics Express | Year: 2015

White organic light-emitting diodes (WOLEDs) resemble light more naturally, with emission spectrum that is comfortable to the human eye. The transparent WOLEDs can be almost invisible by day and can emit a pleasant diffused light at night, allowing the surface light source to shine in both directions, an exciting new lighting technology that could bring new device concepts. However, undesirable angular-dependent emission in transparent WOLEDs is often observed, due to the microcavity effect. In this work, the emission behavior of dual-side emissive transparent WOLEDs was studied experimentally and theoretically. It is found that avoidance of the overlap between the peak wavelengths of the emitters and the resonant wavelength of the organic microcavity moderates the angulardependent electroluminescence emission behavior, thereby improving the color stability of the transparent white WOLEDs over a broad range of the viewing angle. © 2015 Optical Society of America.


Zhang C.,CAS Changchun Institute of Applied Chemistry | Zhang C.,Hebei University | Lin J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2012

Luminescent materials have found a wide variety of applications, including information displays, lighting, X-ray intensification and scintillation, and so on. Therefore, much effort has been devoted to exploring novel luminescent materials so far. In the past decade, defect-related luminescent materials have inspired intensive research efforts in their own right. This kind of luminescent material can be basically classified into silica-based materials, phosphate systems, metal oxides, BCNO phosphors, and carbon-based materials. These materials combine several favourable attributes of traditional commercially available phosphors, which are stable, efficient, and less toxic, being free of the burdens of intrinsic toxicity or elemental scarcity and the need for stringent, intricate, tedious, costly, or inefficient preparation steps. Defect-related luminescent materials can be produced inexpensively and on a large scale by many approaches, such as sol-gel process, hydro(solvo)thermal reaction, hydrolysis methods, and electrochemical methods. This review article highlights the recent advances in the chemical synthesis and luminescent properties of the defect-related materials, together with their control and tuning, and emission mechanisms (solid state physics). We also speculate on their future and discuss potential developments for their applications in lighting and biomedical fields. This journal is © The Royal Society of Chemistry 2012.


Zhang B.,CAS Changchun Institute of Applied Chemistry | Tan G.,Hong Kong Baptist University | Lam C.-S.,Hong Kong Baptist University | Yao B.,CAS Changchun Institute of Applied Chemistry | And 7 more authors.
Advanced Materials | Year: 2012

An extremely high-efficiency solution-processed white organic light-emitting diode (WOLED) is successfully developed by simultaneously using an ideal dendritic host material and a novel efficient orange phosphorescent iridium complex. The optimized device exhibits forward-viewing efficiencies of 70.6 cd A -1, 26.0%, and 47.6 lm W -1 at a luminance of 100 cd m -2, respectively, promising the low-cost solution-processed WOLEDs a bright future as the next generation of illumination sources. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang J.,Hong Kong Baptist University | Zhao F.,CAS Changchun Institute of Applied Chemistry | Zhu X.,Hong Kong Baptist University | Wong W.-K.,Hong Kong Baptist University | And 2 more authors.
Journal of Materials Chemistry | Year: 2012

Some new symmetric and asymmetric platinum(ii) Schiff base complexes with bulky substituents such as tert-butyl and triphenylamino groups have been synthesized which effectively reduced the aggregation or excimer formation. Using selected complexes as phosphorescent emitting materials, yellow light-emitting devices were fabricated with improved efficiency compared with the previously reported analogues. In addition, the phosphorescent white organic light-emitting device (WOLED) was fabricated using a single emissive layer composed of yellow- and blue-emitting materials. © The Royal Society of Chemistry 2012.


Lai J.,CAS Changchun Institute of Applied Chemistry | Lai J.,University of Chinese Academy of Sciences | Luque R.,CAS Changchun Institute of Applied Chemistry | Luque R.,University of Cordoba, Spain | Xu G.,CAS Changchun Institute of Applied Chemistry
ChemCatChem | Year: 2015

Pt-based bimetallic alloy nanomaterials with a low Pt loading can exhibit promising catalytic properties with exciting electrochemical applications. An effective structure control of Pt-based bimetallic alloy nanomaterials is critical to achieve enhanced catalytic properties. This review article focuses on recent advances in the controllable synthesis and electrocatalytic applications of Pt-based bimetallic alloy nanostructures. Recent contributions on the controllable synthesis of a rich variety of Pt-based bimetallic alloy nanostructures, for example, PtPd, PtCu, PtNi, PtCo, and PtFe, and hybrid nanostructures based on Pt-based bimetallic alloy nanomaterials are summarized. Different Pt-based bimetallic alloy nano-electrocatalysts with enhanced activity and durability for different electrocatalytic reactions, such as the fuel cell reaction and the hydrogen evolution reaction, are outlined. Finally, an outlook on future trends and developments is provided. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li G.,CAS Changchun Institute of Applied Chemistry | Li G.,Wuhan University | Lin J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2014

Nowadays there are several technologies used for flat panel displays (FPDs) and the development of FPDs with enhanced energy efficiency and improved display quality is strongly required. Field emission displays (FEDs) have been considered as one of the most promising next generation flat panel display technologies due to their excellent display performance and low energy consumption. For the development of FEDs, phosphors are irreplaceable components. In the past decade, the study of highly efficient low-voltage cathodoluminescent materials, namely FED phosphors, has become the focus of enhancing energy efficiency and realizing high-quality displays. This review summaries the recent progress in the chemical synthesis and improvement of novel, rare-earth and transition metal ions activated inorganic cathodoluminescent materials in powder and thin film forms. The discussion is focused on the modification of morphology, size, surface, composition and conductivity of phosphors and the corresponding effects on their cathodoluminescent properties. Special emphases are given to the selection of host and luminescent centers, the adjustment of emission colors through doping concentration optimization, energy transfer and mono- or co-doping activator ions, the improvement of chromaticity, color stability and color gamut as well as the saturation behavior and the degradation behavior of phosphors under the excitation of a low-voltage electron beam. Finally, the research prospects and future directions of FED phosphors are discussed with recommendations to facilitate the further study of new and highly efficient low-voltage cathodoluminescent materials. This journal is © the Partner Organisations 2014.


Lu Y.,CAS Changchun Institute of Applied Chemistry | An L.,CAS Changchun Institute of Applied Chemistry | Wang S.-Q.,University of Akron | Wang Z.-G.,CAS Changchun Institute of Applied Chemistry | Wang Z.-G.,California Institute of Technology
ACS Macro Letters | Year: 2014

Using Brownian dynamics simulation, we determine the chain orientation and stretching and their connection to stress overshoot in an entangled polymer melt undergoing startup shear at rates lower than the reciprocal of the Rouse time yet higher than the reciprocal of the reptation time. In this rate regime, the prevailing tube theory attributes the stress overshoot to alignment of the primitive chain. In contrast, our results reveal that there is substantial chain stretching that persists well beyond the Rouse time, and it contributes significantly to the initial stress growth. In particular, stress overshoot is found to be primarily due to chain retraction after considerable stretching rather than chain orientation. © 2014 American Chemical Society.


Nakamura I.,CAS Changchun Institute of Applied Chemistry | Wang Z.-G.,California Institute of Technology
ACS Macro Letters | Year: 2014

We provide a perspective on the thermodynamics of salt-doped block copolymer electrolytes consisting of ion-conducting and inert blocks, taking poly(ethylene oxide)-b-polystyrene and lithium salts as an example. We focus on the origin for enhanced immiscibility between the constituent blocks upon addition of lithium salts and discuss issues from selected experiments and from our recent self-consistent field study. © 2014 American Chemical Society.


Huang J.,Wuhan University | Sun N.,CAS Changchun Institute of Applied Chemistry | Yang J.,Wuhan University | Tang R.,Wuhan University | And 3 more authors.
Advanced Functional Materials | Year: 2014

Great efforts have been devoted to seek novel approaches for constructing blue fl uorescent materials, which is one of the most important prerequisites for the commercialization of OLEDs. In recent years, various outstanding luminogens with aggregation-induced emission characteristic exhibit promising applications as emitters, but blue AIE fl uorophores with excellent EL performance are still very scarce. Here, fi ve hole-dominated blue AIE molecules are demonstrated by adopting construction approaches of changing linkage modes and increasing intramolecular torsion together, with the aim to restrict conjugation lengths without sacrifi cing good EL data. Device results show that the novel synthesized materials could be applied as bifunctional materials, namely blue light-emitting and hole-transporting materials, with comparable EL efficiencies, and the ηC,max and ηext,max are up to 8.03 cd A-1 and 3.99% respectively, which is among the best EL performance for blue AIE luminogens. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA.


Aldred M.P.,Huazhong University of Science and Technology | Li C.,Huazhong University of Science and Technology | Zhang G.-F.,Huazhong University of Science and Technology | Gong W.-L.,Huazhong University of Science and Technology | And 4 more authors.
Journal of Materials Chemistry | Year: 2012

We report the synthesis of novel amorphous fluorene-based fluorophores that have been end-capped with tetraphenylethene (TPE). Although in the solid state the fluorophores show bright cyan fluorescence with high (68%) photoluminescence quantum efficiency (PLQE), strong fluorescence quenching is observed in solution with low PLQE values ranging from 0.3% to 2.1%. When the fluorophores were added to a 90% water-THF solvent mixture nanoparticles were formed, which was confirmed by Dynamic Light Scattering (DLS) and Atomic Force Microscopy (AFM). Subsequent fluorescence measurements reveal that all the fluorophores exhibit aggregation induced emission (AIE) with high PLQE (41%). We have carried out a comparative study of 5 fluorene-based TPE materials (F(1-5)TPE), in which the fluorene core is extended, and investigated their thermal, optical, electrochemical and electroluminescence properties. From fluorescence quantum yield data we have discovered that the AIE effect decreases as the fluorene core increases both in the nanoparticle and in the solid state. Thermal analysis reveals that all fluorophores are amorphous with high thermal stabilities. Potential application in solid state vapour sensing has been demonstrated using dichloromethane that shows "on" and "off" fluorescence behaviour. Finally, Organic Light Emitting Diodes (OLEDs) have been fabricated with device configuration ITO/PEDOT/F(1-5)TPE/TPBi/LiF/Al. The best OLED device that incorporates F1-TPE as the emitter exhibits a turn-on voltage of 5.8 V, L max = 1300 cd m -2, η P,max = 1 lm W -1 and η C,max = 2.6 cd A -1. © 2012 The Royal Society of Chemistry.


Huang J.,Hubei University | Sun N.,CAS Changchun Institute of Applied Chemistry | Yang J.,Hubei University | Tang R.,Hubei University | And 4 more authors.
Journal of Materials Chemistry | Year: 2012

In this paper, three benzene-cored fluorophors with TPE moiety peripheries (PhTPE, Ph2TPE and Ph3TPE), are synthesized and their thermal, optical and electronic properties are investigated. All of them are nearly non-emissive when readily dissolved in solution but become highly emissive in the aggregate state, making them promising candidates for optoelectronic materials. Non-doped OLEDs with these luminogens as emissive layers exhibit sky-blue to deep blue emissions from 488 to 457 nm with L max, η C, max and η P, max up to 3966 cd m -2, 5.0 cd A -1 and 3.87 lm W -1, respectively, owing to the twisted conformation between the benzene core and TPE units. © 2012 The Royal Society of Chemistry.


Zou Y.,Hubei University | Ye T.,CAS Changchun Institute of Applied Chemistry | Ma D.,CAS Changchun Institute of Applied Chemistry | Qin J.,Hubei University | Yang C.,Hubei University
Journal of Materials Chemistry | Year: 2012

Two new hole-transporting materials, namely HFB-Cz and HFB-Dpa, were designed and synthesized by attaching carbazole and diphenylamine units to the hexakis(9,9-dihexyl-9H-fluoren-2-yl)benzene (HFB) core via Buchwald-Hartwig coupling reaction. The long alkyl chain and core rigidity endow these compounds with good solution processability and high thermal stability. HFB-Cz and HFB-Dpa exhibit significantly high glass transition temperatures (225 and 154 °C) relative to widely used hole-transporting materials, such as N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4, 4′-diamine (TPD, 65 °C) and 1,4-bis((1-naphthylphenyl)amino)biphenyl (NPB, 96 °C). Solution-processed green OLED devices using HFB-Cz and HFB-Dpa as hole-transporting materials exhibit very high efficiencies with a maximum current efficiency up to 6.2 cd A-1. These efficiencies are substantially higher than the NPB-based control device, and are among the highest for the hole-transporting materials in similar device configuration. © The Royal Society of Chemistry 2012.


Ottakam Thotiyl M.M.,University of St. Andrews | Freunberger S.A.,University of St. Andrews | Freunberger S.A.,University of Graz | Peng Z.,University of St. Andrews | And 4 more authors.
Nature Materials | Year: 2013

Rechargeable lithium-air (O2) batteries are receiving intense interest because their high theoretical specific energy exceeds that of lithium-ion batteries. If the Li-O2 battery is ever to succeed, highly reversible formation/decomposition of Li2O2 must take place at the cathode on cycling. However, carbon, used ubiquitously as the basis of the cathode, decomposes during Li2O2 oxidation on charge and actively promotes electrolyte decomposition on cycling. Replacing carbon with a nanoporous gold cathode, when in contact with a dimethyl sulphoxide-based electrolyte, does seem to demonstrate better stability. However, nanoporous gold is not a suitable cathode; its high mass destroys the key advantage of Li-O2 over Li ion (specific energy), it is too expensive and too difficult to fabricate. Identifying a suitable cathode material for the Li-O2 cell is one of the greatest challenges at present. Here we show that a TiC-based cathode reduces greatly side reactions (arising from the electrolyte and electrode degradation) compared with carbon and exhibits better reversible formation/decomposition of Li2O 2 even than nanoporous gold (>98% capacity retention after 100 cycles, compared with 95% for nanoporous gold); it is also four times lighter, of lower cost and easier to fabricate. The stability may originate from the presence of TiO2 (along with some TiOC) on the surface of TiC. In contrast to carbon or nanoporous gold, TiC seems to represent a more viable, stable, cathode for aprotic Li-O2 cells. © 2013 Macmillan Publishers Limited. All rights reserved.


Liu D.,CAS Changchun Institute of Applied Chemistry | Guo Q.,CAS Changchun Institute of Applied Chemistry | Hou H.,Jiangxi Normal University | Niwa O.,Japan National Institute of Advanced Industrial Science and Technology | You T.,CAS Changchun Institute of Applied Chemistry
ACS Catalysis | Year: 2014

Novel bimetallic PdxCoy alloy nanoparticle (NP)/carbon nanofiber (CNF) composites with superior electrocatalytic performances were successfully prepared by electrospinning Pd and Co precursors, i.e., Pd(acac)2 and Co(acac)2, in polyacrylonitrile followed by a thermal treatment. Uniform dispersion of PdxCo y nanoparticles in carbon nanofibers was achieved. Chemical composition and size of the resulting PdxCoy NPs, which showed a substantial effect on the electrocatalytic properties of Pd xCoy/CNF nanocomposites, can be readily controlled by adjusting the feed ratio of metal precursors. In comparison with commercial Pd/C and other state-of-the-art Pd- or Pt-based catalysts, PdxCo y/CNF nanocomposites prepared in this study exhibited much higher electrocatalytic activity and stability in formic acid and methanol oxidation reactions. This improved electrocatalytic performance is very attractive for fuel cell applications and can be attributed to the unique bimetallic Pd-Co alloy formation, a modified electronic structure of Pd in PdxCo y, as well as uniform dispersion and firm embedment of Pd xCoy NPs in CNF. © 2014 American Chemical Society.


Sun N.,CAS Changchun Institute of Applied Chemistry | Wang Q.,Xi'an Jiaotong University | Zhao Y.,Nanyang Technological University | Chen Y.,Case Western Reserve University | And 4 more authors.
Advanced Materials | Year: 2014

By using mixed hosts with bipolar transport properties for blue emissive layers, a novel phosphorescence/fluorescence hybrid white OLED without using an interlayer between the fluorescent and phosphorescent regions is demonstrated. The peak EQE of the device is 19.0% and remains as high as 17.0% at the practical brightness of 1000 cd m-2. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lu G.,CAS Changchun Institute of Applied Chemistry | Lu G.,University of Massachusetts Amherst | Bu L.,University of Massachusetts Amherst | Li S.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Advanced Materials | Year: 2014

Thermoelectric properties of conjugated polymers are found to improve upon homogeneously distributing conjugated polymer into an insulating supporting matrix. The local one-dimensional charge transport along the interpenetration conductive network simultaneously leads to lower thermal conductivity, higher electrical conductivity without sacrifice of Seebeck coefficient, and thus a higher figure of merit ZT, as compared with neat conjugated polymer. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang X.,CAS Changchun Institute of Applied Chemistry | Wang H.,University of South Carolina | Su Z.,CAS Changchun Institute of Applied Chemistry
Langmuir | Year: 2012

A new synthetic strategy has been developed for the fabrication of Au-Ag bimetallic core-shell nanoparticles (NPs) using polyelectrolyte multilayers (PEMs) as unique nanoreactors. Bimetallic NPs composed of Au core and Ag shell were successively incorporated into PEMs by repeating anion/cation exchange/reduction cycle multiple times in a stepwise manner. The strategy described here allows for the facile preparation of Au@Ag core-shell NPs with well-controlled core and shell dimensions and geometrically tunable optical properties by simply varying the number of ion-exchange/reduction cycles in the PEM matrix. The strategy can be extended to synthesize in situ other core-shell NPs in polymer matrix. © 2012 American Chemical Society.


Su Z.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
Angewandte Chemie - International Edition | Year: 2010

Re-engineer the core: The genomic core of a virus (left) can be re-engineered by the coassembly of viral coat proteins and DNA amphiphiles to produce virus-like nanocarriers to transport both hydrophobic and hydrophilic compounds. It is a general strategy for adapting virus-based vehicles for drug-delivery applications. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zan X.,University of South Carolina | Feng S.,University of South Carolina | Balizan E.,University of South Carolina | Lin Y.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
ACS Nano | Year: 2013

A facile and robust method to align one-dimensional (1D) nanoparticles (NPs) in large scale has been developed. Using flow assembly, representative rod-like nanoparticles, including tobacco mosaic virus (TMV), gold nanorods, and bacteriophage M13, have been aligned inside glass tubes by controlling flow rate and substrate surface properties. The properties of 1D NPs, such as stiffness and aspect ratio, play a critical role in the alignment. Furthermore, these hierarchically organized structures can be used to support cell growth and control the cell orientation and morphology. When C2C12 myoblasts were cultured on surfaces coated with aligned TMV, we found that nanoscale topographic features were critical to guide the cell orientation and myogenic differentiation. This method can therefore be used in the fabrication of complex assemblies with 1D NPs and have wide applications in tissue engineering, sensing, electronics, and optical fields. © 2013 American Chemical Society.


Zhang L.,CAS Changchun Institute of Applied Chemistry | Zhang Z.,CAS Changchun Institute of Applied Chemistry | Zhang Z.,University of Chinese Academy of Sciences | He C.,Nanyang Normal University | And 3 more authors.
ACS Nano | Year: 2014

Mass production of graphene with low cost and high throughput is very important for practical applications of graphene materials. The most promising approach to produce graphene with low defect content at a large scale is exfoliation of graphite in an aqueous solution of surfactants. Herein, we report a molecular design strategy to develop surfactants by attaching ionic groups to an electron-deficient π-conjugated unit with flexible alkyl spacers. The molecular design strategy enables the surfactant molecules to interact strongly with both the graphene sheets and the water molecules, greatly improving graphene dispersion in water. As the result, a few-layered graphene concentration as high as 1.2-5.0 mg mL-1 is demonstrated with the surfactant, which is much higher than those (<0.1 mg mL-1) obtained with normal aromatic or nonaromatic surfactants. Moreover, the surfactant can be easily synthesized at large scale. The superior performance and convenient synthesis make the surfactant very promising for mass production of graphene. © 2014 American Chemical Society.


Wang L.,Jiangxi Normal University | Zheng Y.,Jiangxi Normal University | Lu X.,Jiangxi Normal University | Li Z.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Sensors and Actuators, B: Chemical | Year: 2014

A novel nonenzymatic glucose sensor was developed by electrodepositing dendritic copper-cobalt nanostructures (Cu-Co NSs) on glassy carbon electrode (GCE) which was modified by reduced grapheme oxide-chitosan (RGO-CHIT) nanocomposites. The electrochemical behaviors and electrocatalytic performances of the sensor towards oxidation of glucose were evaluated by cyclic voltammograms, chronoamperometry and amperometric method. Compared to sensors based on monometal Cu or Co NSs, the sensor based on bimetal Cu-Co NSs exhibits good electrocatalytic activity towards oxidation of glucose. The effects of electrodeposition time and the ratio of Cu2+ and Co2+ in an electrodeposition solution on the electrocatalytic performance of the Cu-Co NSs sensor were explored in detail. The best catalytic activity towards oxidation of glucose can be achieved under an optimized condition: electrodepositing time of 2600 s and the Cu2+/Co2+ molar ratio of 2:1. The catalytic current density is linear to the glucose concentration in the range of 0.015-6.95 mM (r = 0.9947) with a sensitivity of 1921 μA cm-2 mM-1, and a detection limit of 10 μM. The good catalytic activity, high sensitivity and good stability indicate that the newly developed sensor based on the dendritic Cu-Co NSs/RGO-CHIT/GCE is a promising sensor for application in real samples. © 2014 Elsevier B.V.


Gong S.,Hubei University | Fu Q.,CAS Changchun Institute of Applied Chemistry | Zeng W.,Hubei University | Zhong C.,Hubei University | And 3 more authors.
Chemistry of Materials | Year: 2012

A series of oxadiazole/arylamine hybrids, namely pOXDDSiPA, pOXDDSiCz, mOXDDSiPA, and mOXDDSiCz, were designed and synthesized by incorporating electron-donating diphenylamine or 3,6-di-tert-butyl-9H-carbazole unit and electron-accepting oxadiazole moiety into one molecule via double-silicon-bridged linkage. This design strategy of extending molecular structure endows these compounds with good solution processability, and high thermal and morphological stability, without lowering their triplet energies. These compounds exhibit similar energy levels and higher glass transition temperatures (92-190 °C) relative to the corresponding single-silicon-bridged congeners. The reasonable combination of the tetra-meta-position linking topology and electron donor diphenylamine group imparts the compound mOXDDSiPA with both relative high triplet energy (2.72 eV) and high-lying HOMO level (5.30 eV). As a result, the best EL performance was achieved for the mOXDDSiPA-based blue phosphorescent device, with a maximum current efficiency of 23.4 cd A-1, a maximum power efficiency of 10.2 lm W-1, and a maximum external quantum efficiency of 10.7%. Moreover, the current efficiency remains as high as 23.3 cd A-1 at the luminance of 100 cd m-2, and even at the high luminance of 1000 cd m-2, the efficiency is still 17.7 cd A-1. © 2012 American Chemical Society.


Su M.,CAS Changchun Institute of Applied Chemistry | Huang H.,CAS Changchun Institute of Applied Chemistry | Ma X.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina | Su Z.,CAS Changchun Institute of Applied Chemistry
Macromolecular Rapid Communications | Year: 2013

Self-assembly of poly(2-vinylpyridine)-block-poly(ε-caprolactone) (P2VP-b-PCL) diblock copolymer in the presence of a selective solvent is investigated by transmission electron microscopy and atomic force microscopy. Addition of water into a P2VP-b-PCL solution in N,N-dimethylformamide at 20 °C produces elongated truncated lozenge shaped single crystals of uniform size and shape in large quantities. The single crystals are composed of PCL single-crystal layer sandwiched between two P2VP layers tethered on the top and bottom basal surfaces. The formation of the single crystals is found to depend on the temperature. These findings provide a facile approach to the preparation of uniform single crystals in large quantities. Single crystals of uniform shape and size in large quantities can be obtained via self-assembly of a coil-crystalline block copolymer by simply adding a selective solvent into the copolymer solution. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lu Y.,CAS Changchun Institute of Applied Chemistry | An L.,CAS Changchun Institute of Applied Chemistry | Wang S.-Q.,University of Akron | Wang Z.-G.,California Institute of Technology
ACS Macro Letters | Year: 2013

Using Brownian dynamics simulation, we determine chain dimensions in an entangled polymer melt undergoing startup shear at a rate lower than the reciprocal of the Rouse time yet higher than the reciprocal reptation time. Here the tube model expects negligible chain stretching. In contrast, our simulation shows the deformed coil to conform closely to affine deformation. We find that the total number of entanglements decreases with increasing shear. Remarkably, up to many Rouse time, the decline in the number of initial entanglements is slower than that under the quiescent condition. These results point to fundamental deficiencies in the molecular picture of the tube model for startup shear. © 2013 American Chemical Society.


Tao Y.,Hubei University | Wang Q.,CAS Changchun Institute of Applied Chemistry | Yang C.,Hubei University | Zhong C.,Hubei University | And 2 more authors.
Advanced Functional Materials | Year: 2010

A new triphenylamine/oxadiazole hybrid, namely m-TPA-o-OXD, formed by connecting the meta-position of a phenyl ring in triphenylamine with the ortho-position of 2,5-biphenyl-1,3,4-oxadiazole, is designed and synthesized. The new bipolar compound is applicable in the phosphorescent organic light-emitting diodes (PHOLEDs) as both host and exciton-blocking material. By using the new material and the optimization of the device structures, very high efficiency green and yellow electrophosphorescence are achieved. For example, by introducing 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI) to replace 2, 9-dimethyl-4,7-diphenyl-1, 10-phenanthroline (BCP)/tris(8-hydroxyquinoline) aluminium (Alq3) as hole blocking/electron transporting layer, followed by tuning the thicknesses of hole-transport 1, 4-bis[(1-naphthylphenyl) amino]biphenyl (NPB) layer to manipulate the charge balance, a maximum external quantum efficiency (ηEQE,max) of 23.0% and a maximum power efficiency (ηp,max) of 94.3 lm W-1 are attained for (ppy)2Ir(acac) based green electrophosphorescence. Subsequently, by inserting a thin layer of m-TPA-o-OXD as self triplet exciton block layer between hole-transport and emissive layer to confine triplet excitons, a ηEQE,max of 23.7% and ηp,max of 105 lm W -1 are achieved. This is the highest efficiency ever reported for (ppy)2 Ir(acac) based green PHOLEDs. Furthermore, the new host m-TPA-o-OXD is also applicable for other phosphorescent emitters, such as green-emissive Ir(ppy)3 and yellow-emissive (fbi)2 Ir(acac). A yellow electrophosphorescent device with ηEQE,max of 20.6%, ηc,max of 62.1 cd A-1, and η p,max of 61.7 lm W-1, is fabricated. To the author's knowledge, this is also the highest effi ciency ever reported for yellow PHOLEDs. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Tao Y.,Hubei University | Wans Q.,CAS Changchun Institute of Applied Chemistry | Yang C.,Hubei University | Zhong C.,Hubei University | And 3 more authors.
Advanced Functional Materials | Year: 2010

A series of bipolar transport host materials: 2,5-bis(2-(9H-carbazol-9-yl) phenyl)-1, 3, 4-oxadiazole (o-CzOXD) (1), 2,5-bis(4-(9H-carbazo(-9-yI)phenyl)-l, 3, 4-oxadiazole (p-CzOXD) (2), 2,5-bis(3-(9H-carbazoI-9-yl)phenyI)-l, 3, 4-oxadiazole (m-CzOXD) (3) and 2-p-(9H-carbazol-9-yl)phenyI)-5-(4-(9H-carbazoI- 9-yllphenyl)-1, 3, 4-oxadiazole (op-CzOXD) (4) are synthesized through simple arp,atoc nucleophtic substitution reactions. The incorporation of the oxadiazole moiety greatly improves their morphological stability, with Td and Tg in the range of 428-4640C and 97-133 °C, respectively. The ortho and meta positions of the 2, 5- dipheny intramolecular charge transfer and a higher triplet energy compared to the paraposition linked analogue (2). The four compounds exhibit similar LUMO levels (2.55-2.59eV) to other oxadiazole derivatives, whereas the HOMO levas vary in a range from 5.55 eV to 5.69eV, depending on the linkage modes. DFT. calculation results indiote that 1, 3, and 4 have almost complete separation of their HOMO and LUMO levels at the hole- and electron-transporting moieties, while 2 exhibits only partial separation of the HOMO and LUMO levels possibly due to intramolecular charge transfer. Phosphorescent organic light-emitting devices fabricated using 1-4 as hosts and a green emitter, lr(ppy)3 or (ppy)2 lr(acac), as the guest exhibit good to excellent performance Devices hosted by o-CzOXD (1) achieve maximum current efficiencies (ηc) as high as 77.9 cd A-1 for (ppy)2lr(acac). The excellent device performance may be attributed to the well-matched energy levels between the host and hole-transport layers, the high triplet energy of the host and the complete spatial separation of HOMO and LUMO energy levels. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.


Chen Y.,University of St. Andrews | Freunberger S.A.,University of St. Andrews | Freunberger S.A.,University of Graz | Peng Z.,University of St. Andrews | And 4 more authors.
Nature Chemistry | Year: 2013

The non-aqueous Li-air (O2) battery is receiving intense interest because its theoretical specific energy exceeds that of Li-ion batteries. Recharging the Li-O2 battery depends on oxidizing solid lithium peroxide (Li2O2), which is formed on discharge within the porous cathode. However, transporting charge between Li 2O2 particles and the solid electrode surface is at best very difficult and leads to voltage polarization on charging, even at modest rates. This is a significant problem facing the non-aqueous Li-O2 battery. Here we show that incorporation of a redox mediator, tetrathiafulvalene (TTF), enables recharging at rates that are impossible for the cell in the absence of the mediator. On charging, TTF is oxidized to TTF+ at the cathode surface; TTF+ in turn oxidizes the solid Li2O 2, which results in the regeneration of TTF. The mediator acts as an electron-hole transfer agent that permits efficient oxidation of solid Li 2O2. The cell with the mediator demonstrated 100 charge/discharge cycles. © 2013 Macmillan Publishers Limited.


Chen Y.,Case Western Reserve University | Lin W.-C.,Case Western Reserve University | Liu J.,CAS Changchun Institute of Applied Chemistry | Dai L.,Case Western Reserve University
Nano Letters | Year: 2014

Tandem polymer solar cells (PSCs), consisting of more than one (normally two) subcells connected by a charge recombination layer (i.e., interconnecting layer), hold great promise for enhancing the performance of PSCs. For an ideal tandem solar cell, the open circuit voltage (Voc) equals to the sum of those of the subcells while keeping the short circuit current the same as the lower one, leading to an increased overall power conversion efficiency. The interconnecting layer plays an important role in regulating the tandem device performance. Here, we report that graphene oxide (GO)/GO-Cs (cesium neutralized GO) bilayer modified with ultrathin Al and MoO3 can act as an efficient interconnecting layer in tandem PSCs to achieve a significantly increased Voc, reaching almost 100% of the sum of the subcell V ocs under standard AM 1.5 conditions. © 2014 American Chemical Society.


Lin Y.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
ChemBioChem | Year: 2014

A peptide substrate for transglutaminase factor XIII (FXIIIa) can be caged with a photo-deprotectable group and immobilized to the hydrogel framework. The substrate can be decaged by using multiphoton light to anchor cell-signaling motifs in a spatial specific manner.


Lin Y.,CAS Changchun Institute of Applied Chemistry | Wang Q.,University of South Carolina
Angewandte Chemie - International Edition | Year: 2012

K(l)ick it into reverse: Mechanical force (ultrasound) may be employed to promote a retrocycloaddition reaction of a 1,2,3-triazole to regenerate the parent azide and alkyne, a reaction that cannot be achieved by other means. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Guo Q.,CAS Changchun Institute of Applied Chemistry | Huang J.,CAS Changchun Institute of Applied Chemistry | Chen P.,Jiangxi Normal University | Liu Y.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Sensors and Actuators, B: Chemical | Year: 2012

In this paper, the simultaneous determination of dihydroxybenzene isomers (catechol (CC) and hydroquinone (HQ)) was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) at electrospun carbon nanofiber-modified carbon paste electrode (ECF-CPE) in 0.1 M PBS (pH 7.0) solution. The ECF was prepared by combination of electrospinning and thermal treatment processes, and was modified on the surface of CPE directly without further oxidation treatment and immobilization. Compared to the bare CPE electrode, ECF-CPE exhibits much higher electrocatalytic activity toward the oxidation of dihydroxybenzene isomers with increasing of peak current and decreasing of potential difference (ΔE p) between the oxidation and reduction peaks. CV and DPV results show that the isomers can be detected selectively and sensitively at modified CPE with peak-to-peak separation about 110 mV. Under the optimized condition, the detection limits of CC and HQ are 0.2 and 0.4 μM (S/N = 3) with linear ranges of 1-200 μM in the presence of 50 μM isomer, respectively. The proposed method was successfully applied to the simultaneous determination of CC and HQ in real sample of lake water with reliable recovery. The attractive electrochemical performances and facile preparation method made this novel electrode promising for the development of effective dihydroxybenzene sensor. Copyright © 2012 Published by Elsevier B.V. All rights reserved.


Lu Y.,CAS Changchun Institute of Applied Chemistry | An L.,CAS Changchun Institute of Applied Chemistry | Wang Z.-G.,California Institute of Technology
Macromolecules | Year: 2013

We present a general theory for the intrinsic viscosity of flexible polymers of arbitrary architecture. The theory is based on a partially permeable sphere model for which we introduce two phenomenological functions, the drag function ξ and the drainage function κ, that are determined by the density profile of the polymer. At the mean-field level, these functions capture the long-range, multibody, accumulative hydrodynamic interactions, that are responsible for the frictional dissipation in and around a polymer. The density profiles for a diversity of chain architectures are obtained by Monte Carlo simulation. Predictions from our theory are in good agreement with experimental data on all the polymer structures examined, ranging from linear, ring, and stars to hyperbranched and dendrimers. The concepts and methods we introduce in this work should be useful for studying other dilute solution frictional properties, such as the self-diffusivity, and provide a convenient framework for understanding the relationship between the molecular architecture and their dilute solution properties. © 2013 American Chemical Society.


Liu C.,Hubei University | Fu Q.,CAS Changchun Institute of Applied Chemistry | Zou Y.,Hubei University | Yang C.,Hubei University | And 2 more authors.
Chemistry of Materials | Year: 2014

Two new star-shaped oligofluorenes, HFB-diF-Dpa and HFB-terF-Dpa, with a hexakis(fluoren-2-yl)benzene core and six diphenylamine end-cappers were designed and synthesized. The peripheral diphenylamine groups enhance the HOMO energy levels of the materials, and the bulky star-shaped structures efficiently suppress the intermolecular interaction. Their thermal, photophysical, and electrochemical properties were investigated. The two compounds display strong deep-blue emission both in solution and solid state. Solution-processed devices based on these starbursts exhibit highly efficient and stable deep-blue electroluminescence. Their high-lying HOMO energy levels match very well with that of the hole-injecting material. The double-layered device featuring HFB-diF-Dpa as emitter shows a low turn-on voltage of 3.6 V, a maximum current efficiency of 6.99 cd A-1, and a maximum external quantum efficiency of 5.45% with the CIE coordinate of (0.154, 0.136). In particular, the combination of low driving voltage and high EQE provides an outstanding maximum power efficiency of 6.10 lm W-1, which is the highest for nondoped deep-blue OLEDs based on solution-processable materials. Moreover, these devices present small values of efficiency roll-off at high brightness up to 1000 cd m-2. © 2014 American Chemical Society.


Sun X.,CAS Changchun Institute of Applied Chemistry | Sun X.,University of Chinese Academy of Sciences | Zhang Y.,CAS Changchun Institute of Applied Chemistry | Song P.,CAS Changchun Institute of Applied Chemistry | And 4 more authors.
ACS Catalysis | Year: 2013

For the goal of practical industrial development of fuel cells, inexpensive, sustainable, and high performance electrocatalysts for oxygen reduction reactions (ORR) are highly desirable alternatives to platinum (Pt) and other rare materials. In this work, sustainable fluorine (F)-doped carbon blacks (CB-F) as metal-free, low-cost, and high-performance electrocatalysts for ORR were synthesized for the first time. The performance (electrocatalytic activity, long-term operation stability, and tolerance to poisons) of the best one (BP-18F, based on Black Pearls 2000 (BP)) is on the same level as Pt-based or other best non-Pt-based catalysts in alkaline medium. The maximum power density of alkaline direct methanol fuel cell with BP-18F as the cathode (3 mg/cm2) is ∼15.56 mW/cm2 at 60 C, compared with a maximum of 9.44 mW/cm2 for commercial Pt/C (3 mgPt/cm 2). All these results unambiguously demonstrate that these sustainable CB-F catalysts are the most promising alternatives to Pt in an alkaline fuel cell. Since sustainable carbon blacks are 10 000 times less expensive and much more abundant than Pt or other rare materials, these CB-F electrocatalysts possess the best price/performance ratio for ORR to date. © 2013 American Chemical Society.


Liu Y.,CAS Changchun Institute of Applied Chemistry | Wang D.,CAS Changchun Institute of Applied Chemistry | Xu L.,CAS Changchun Institute of Applied Chemistry | Hou H.,Jiangxi Normal University | You T.,CAS Changchun Institute of Applied Chemistry
Biosensors and Bioelectronics | Year: 2011

A facile wet-chemical method was developed to prepare a novel Pt nanoparticle-loaded carbon nanofiber (Pt/CNF) electrode. Without using any stabilizer or pretreatment procedure, large amounts of Pt nanoparticles could be well deposited on the surface of the electrospun CNF electrode at room temperature, as revealed by scanning electron microscopy (SEM). The effect of the precursor concentration on the formation of Pt catalysts was investigated to optimize the performance of the proposed hybrid electrode. When applied to the electrochemical detection of hydrogen peroxide (H 2O 2), the Pt/CNF electrode exhibited low overpotential, fast response and high sensitivity. A low detection limit of 0.6μM with wide linear range of 1-800μM (R=0.9991) was achieved at the Pt/CNF electrode, which was superior to that obtained with other H 2O 2 electrochemical sensors reported previously. In addition, the Pt/CNF electrode showed good selectivity for H 2O 2 detection in the presence of ascorbic acid (AA), acetaminophenol (AP) and uric acid (UA) under physiological pH condition. The attractive analytical performances and facile preparation method made this novel hybrid electrode promising for the development of effective H 2O 2 sensors. © 2011 Elsevier B.V.


Liu J.,CAS Changchun Institute of Applied Chemistry | Durstock M.,Air Force Research Lab | Dai L.,Case Western Reserve University
Energy and Environmental Science | Year: 2014

Owing to their solution processability, unique two-dimensional structure, and functionalization-induced tunable electronic structures, graphene oxide (GO) and its derivatives have been used as a new class of efficient hole- and electron-extraction materials in polymer solar cells (PSCs). Highly efficient and stable PSCs have been fabricated with GO and its derivatives as hole- and/or electron-extraction layers. In this review, we summarize recent progress in this emerging research field. We also present some rational concepts for the design and development of the GO-based hole- or electron-extraction layers for high-performance PSCs, along with challenges and perspectives. This journal is © the Partner Organisations 2014.


He S.,CAS Changchun Institute of Applied Chemistry | He S.,University of Chinese Academy of Sciences | Hu C.,Jiangxi Normal University | Hou H.,Jiangxi Normal University | Chen W.,CAS Changchun Institute of Applied Chemistry
Journal of Power Sources | Year: 2014

3D carbon materials-supported MnO2 have promising application in energy storage as supercapacitor electrode materials. Here, we demonstrate a simple and scalable method to fabricate 3D carbon paper-supported MnO 2 nanosheets, which can be used as supercapacitor electrode materials with low cost and high capacitance performance. MnO2 nanosheets with thickness about a few nanometers are grown on the carbon paper substrate through the reaction between aqueous KMnO4 and carbon. With the present method, the self-supported MnO2 composites can be fabricated into supercapacitor electrodes directly without any binder and conductive agents. It is found that MnO2 content in the composites increases with the increasing of KMnO4 concentration. The supercapacitor based on the hybrid with a MnO2 content of 7.9% exhibits the largest specific capacitance of 306.6 F g-1 at 0.5 A g-1, and a high power density of 67.8 kW kg-1 at the maximum current density of 300 A g-1. Moreover, the supercapacitors exhibit capacitance retention above 95% after 6000 cycles, demonstrating high stability of the carbon paper-supported MnO2 nanosheets for supercapacitors. Such 3D carbon paper-based architectures have promising application in energy storage devices with high power density and stability. © 2013 Elsevier B.V. All rights reserved.


Fan C.,Hubei University | Zhu L.,CAS Changchun Institute of Applied Chemistry | Liu T.,Hubei University | Jiang B.,Hubei University | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2014

To achieve high efficiencies in blue phosphorescent organic light-emitting diodes (PhOLEDs), the triplet energies (T1) of host materials are generally supposed to be higher than the blue phosphors. A small organic molecule with low singlet energy (S1) of 2.80eV and triplet energy of 2.71eV can be used as the host material for the blue phosphor, [bis(4,6-difluorophenylpyridinato-N,C2′)iridium(III)] tetrakis(1-pyrazolyl)borate (FIr6; T1=2.73eV). In both the photo- and electro-excited processes, the energy transfer from the host material to FIr6 was found to be efficient. In a three organic-layer device, the maximum current efficiency of 37cd A-1 and power efficiency of 40Lm W-1 were achieved for the FIr6-based blue PhOLEDs. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Huang J.,Hubei University | Sun N.,CAS Changchun Institute of Applied Chemistry | Chen P.,Hubei University | Tang R.,Hubei University | And 3 more authors.
Chemical Communications | Year: 2014

By simply introducing additional groups with different size and conjugation degree to the 2,2′-positions of BTPE, four BTPE derivatives are prepared which give blue or deep-blue EL emissions when used as emitters in non-doped OLEDs, as the result of the tuned dihedral angles of the biphenyl cores (up to ∼89°), providing a new approach to design AIE luminogens with blue and deep-blue emissions. This journal is © The Royal Society of Chemistry.


Gong S.,Hubei University | Chen Y.,CAS Changchun Institute of Applied Chemistry | Yang C.,Hubei University | Zhong C.,Hubei University | And 2 more authors.
Advanced Materials | Year: 2010

A molecular design strategy for a bipolar host material is demonstrated by incorporating both electron donor and electron acceptor into a silicon-bridged structure. A two-color, all phosphor and single-emitting-layer white OLED hosted by the new bipolar compound p-BISiTPA is fabricated. The device displays a high efficiency, with ηc, max of 51.8 cd A-1, η p, max of 42.7 lm W-1 and ηext, max of 19.1%. Furthermore, the ηext is still as high as 17.4% at the luminance of 1000 cd m-2, with a rather low roll-off value of 8.9%. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zan X.,CAS Changchun Institute of Applied Chemistry | Kozlov M.,University of Massachusetts Amherst | Kozlov M.,Millipore | McCarthy T.J.,University of Massachusetts Amherst | Su Z.,CAS Changchun Institute of Applied Chemistry
Biomacromolecules | Year: 2010

Covalently attached, soft poly(vinyl alcohol) (PVA) hydrogel films containing silver particles were prepared on solid biodegradable poly(l-lactic acid) (PLLA) samples by a multistep procedure involving oxygen plasma treatment, UV-initiated graft polymerization, and chemical grafting methods. The modification steps were followed and verified using attenuated total reflection infrared spectroscopy and X-ray photoelectron spectroscopy. 2-Hydroxyethyl methacrylate (HEMA) was graft polymerized from the surface of oxygen plasma-treated PLLA film samples and the alcohol functionality in the grafted polyHEMA chains was oxidized using pyridinium dichromate to obtain an aldehyde-rich surface. PVA was then grafted onto this surface using acid catalysis (acetal formation). The "freeze/thaw method" was used to form a PVA hydrogel layer that incorporated the covalently grafted PVA chains in the physically cross-linked gel. This composite film (PLLA-PVA gel) was doped with silver ions, which were reduced to silver using NaBH 4. Scanning electron microscopy of cross sections of PLLA-PVA gel indicates robust attachment of the PVA hydrogel layer to the PLLA film. PLLA-PVA gel/Ag(0) film samples exhibit both antibacterial and reduced cell adhesion properties due to the antibacterial properties of silver nanoparticles and high water content, respectively. This method provides a route to mechanically sound biodegradable materials with tunable soft material surface properties. Potential applications in tissue engineering and biomedical devices are envisioned. © 2010 American Chemical Society.


Zou Y.,Hubei University | Zou J.,South China University of Technology | Ye T.,CAS Changchun Institute of Applied Chemistry | Li H.,Hubei University | And 5 more authors.
Advanced Functional Materials | Year: 2013

Grafting six fluorene units to a benzene ring generates a new highly twisted core of hexakis(fluoren-2-yl)benzene. Based on the new core, six-arm star-shaped oligofluorenes from the first generation T1 to third generation T3 are constructed. Their thermal, photophysical, and electrochemical properties are studied, and the relationship between the structures and properties is discussed. Simple double-layer electroluminescence (EL) devices using T1-T3 as non-doped solution-processed emitters display deep-blue emissions with Commission Internationale de l'Eclairage (CIE) coordinates of (0.17, 0.08) for T1, (0.16, 0.08) for T2, and (0.16, 0.07) for T3. These devices exhibit excellent performance, with maximum current efficiency of up to 5.4 cd A -1, and maximum external quantum efficiency of up to 6.8%, which is the highest efficiency for non-doped solution-processed deep-blue organic light-emitting diodes (OLEDs) based on starburst oligofluorenes, and is even comparable with other solution-processed deep-blue fluorescent OLEDs. Furthermore, T2- and T3-based devices show striking blue EL color stability independent of driving voltage. In addition, using T0-T3 as hole-transporting materials, the devices of indium tin oxide (ITO)/poly(3,4- ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS)/T0-T3/tris(8- hydroxyquinolinato)aluminium (Alq3)/LiF/Al achieve maximum current efficiencies of 5.51-6.62 cd A-1, which are among the highest for hole-transporting materials in identical device structure. Grafting six fluorene units to a benzene ring generates a novel highly twisted core of hexakis(fluoren-2-yl)benzene. The new star-shaped macromolecules T1-T3, based on the propeller-like core, show high efficiency deep-blue emission. T2- and T3-based organic light-emitting diodes (OLEDs) exhibit the highest efficiency for non-doped solution-processed deep-blue OLEDs based on starburst oligofluorenes. These star-shaped oligofluorenes are also demonstrated to be good hole-transporting materials. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gong S.,Hubei University | Fu Q.,CAS Changchun Institute of Applied Chemistry | Wang Q.,CAS Changchun Institute of Applied Chemistry | Yang C.,Hubei University | And 3 more authors.
Advanced Materials | Year: 2011

Phosphorescent organic light-emitting diodes (PhOLEDs) offer a bright future for the next generation flat-panel displays and lighting sources due to their high quantum efficiency compared with fluorescent OLEDs. [1,2] To date, green and red PhOLEDs with 100% internal quantum efficiency have been achieved, [3,4] but highly efficient and stable blue PhOLEDs, especially deepblue PhOLEDs, remain to be further developed. Many works on blue PhOLEDs have focused on the blue phosphor of iridium(III) bis(4,6- (difluorophenyl)pyridine- N , C 2′ ) picolinate (FIrpic). [5-8] Among these, Kido et al. [8] reported the highest external quantum efficiencies (EQE) of 26% and 25% at a practical luminance of 100 and 1000 cd m -2 , respectively. Despite the efficiency improvement for the FIrpic-based blue PhOLEDs, their color purity with Commission International de I'Eclairage (CIE) coordinates of (0.17, 0.34) [5b] is not ideal for the practical applicability of blue PhOLEDs in full-color displays and solid lighting. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li G.,Wuhan University | Tian Y.,Wuhan University | Zhao Y.,Wuhan University | Lin J.,CAS Changchun Institute of Applied Chemistry
Chemical Society Reviews | Year: 2015

Nowadays, phosphor converted white light-emitting diodes (pc-WLEDs) have been widely used in solid-state lighting and display areas due to their superior lifetime, efficiency, and reliability as well as significant reduction in power consumption. Phosphors are indispensable components of pc-WLED devices, and their luminescence properties determine the quality of WLED lighting and displays. In order to further achieve high luminous efficacy, chromatic stability, and color-rending properties in pc-WLEDs, much effort has been focused on improving current pc-WLED phosphors and developing novel pc-WLED phosphors recently. This review article concerns commonly used rare earth ion (Eu2+ and Ce3+) activated inorganic phosphors, highlighting the important effect of spectral tuning via local structural variations on improving the luminescence performance of phosphors. The main spectral tuning strategies are discussed in detail and summarized, including (1) doping level control; (2) cationic substitution; (3) anionic substitution; (4) cationic-anionic substitution; (5) the crystal-site engineering approach; (6) mixing of nanophases. © The Royal Society of Chemistry 2015.


Tang X.,CAS Changchun Institute of Applied Chemistry | Liu Y.,CAS Changchun Institute of Applied Chemistry | Hou H.,Jiangxi Normal University | You T.,CAS Changchun Institute of Applied Chemistry
Talanta | Year: 2010

A novel and simple method for the direct and quantitative determination of L-tryptophan (Trp), L-tyrosine (Tyr) and L-cysteine (Cys) was proposed in this work. Carbon nanofibers (CNFs), made by electrospinning technique, were used to modify carbon paste electrode (CPE) without any treatment to study the electrochemical behaviors of the three amino acids using cyclic voltammetry (CV) and constant potential amperometric method. The results demonstrated that the CNFs modified carbon paste electrode (CNF-CPE) exhibited high electrocatalytic activity and good analytical performance towards the oxidation of the three amino acids. The linear ranges of Trp, Tyr and Cys were 0.1-119, 0.2-107 and 0.15-64 μM with correlation coefficients of 0.9994, 0.9985 and 0.9996, respectively. All the detection limits of the analytes were 0.1 μM (S/N = 3). In addition, the CNF-CPE displayed good reproducibility, high sensitivity and good selectivity towards the determination of the amino acids, making it suitable for the determination of Trp, Tyr and Cys in clinical and medicine. © 2009 Elsevier B.V. All rights reserved.


Gong S.,Hubei University | Chen Y.,CAS Changchun Institute of Applied Chemistry | Luo J.,Hubei University | Yang C.,Hubei University | And 3 more authors.
Advanced Functional Materials | Year: 2011

A series of tetraarylsilane compounds, namely p-BISiTPA (1), m-BISiTPA (2), p-OXDSiTPA (3), m-OXDSiTPA (4), are designed and synthesized by incorporating electron-donating arylamine and electron-accepting benzimidazole or oxadiazole into one molecule via a silicon-bridge linkage mode. Their thermal, photophysical and electrochemical properties can be finely tuned through the different groups and linking topologies. The para-disposition compounds 1 and 3 display higher glass transition temperatures, slightly lower HOMO levels and triplet energies than their meta-disposition isomers 2 and 4, respectively. The silicon-interrupted conjugation of the electron-donating and electron-accepting segments gives these materials the following advantages: i) relative high triplet energies in the range of 2.69-2.73 eV; ii) HOMO/LUMO levels of the compounds mainly depend on the electron-donating and electron-accepting groups, respectively; iii) bipolar transporting feature as indicated by hole-only and electron-only devices. These advantages make these materials ideal universal hosts for multicolor phosphorescent OLEDs. 1 and 3 have been demonstrated as universal hosts for blue, green, orange and white electrophosphorescence, exhibiting high efficiencies and low efficiency roll-off. For example, the devices hosted by 1 achieve maximum external quantum efficiencies of 16.1% for blue, 22.7% for green, 20.5% for orange, and 19.1% for white electrophosphorescence. Furthermore, the external quantum efficiencies are still as high as 14.2% for blue, 22.4% for green, 18.9% for orange, and 17.4% for white electrophosphorescence at a high luminance of 1000 cd m-2. The two-color, all-phosphor white device hosted by 3 acquires a maximum current efficiency of 51.4 cd A-1, and a maximum power efficiency of 51.9 lm W-1. These values are among the highest for single emitting layer white PhOLEDs reported till now. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu Q.-Y.,Jiangxi Normal University | Liu Q.-Y.,CAS Fujian Institute of Research on the Structure of Matter | Wang W.-F.,Jiangxi Normal University | Wang Y.-L.,Jiangxi Normal University | And 3 more authors.
Inorganic Chemistry | Year: 2012

A sulfonate-carboxylate ligand, 4,8-disulfonyl-2,6-naphthalenedicarboxylic acid (H 4-DSNDA), and eight new lanthanide coordination polymers { [ P r 4 ( O H ) 4 ( D S N D A ) 2 ( H 2 O )1 2 ] ( H 2 O )1 0 } n ( 1 ), [ L n (H 2 -DSNDA) 0.5(DSNDA) 0.5(H 2O) 5] n (Ln = La(2), Nd(3), Sm(4), Eu(5), Gd(6), and Dy(7)), and {[Er(H-DSNDA)(H 2O) 4](H 2O)}n (8)have been synthesized. Detailed crystal structures of these compounds have been investigated. Compound 1 has a 3D framework featuring the unique cubane-shaped [Pr 4(μ 3-OH) 4] clusters and is a binodal 4,8-connected network with (4 16·6 12)(4 4·6 2) 2 topology. Compounds 2-7 are isostructural and have 2D layered structures. Compound 8 is also a 2D layer but belongs to different structural types. The luminescence behavior of compound Eu(5)shows that the π-rich aromatic organic ligands efficiently transfer the absorbed light energy to the Eu(III)ions, thus enhancing the overall luminescent properties of compound Eu(5). The magnetic properties of all compounds except for the diamagnetic La(2)compound have been investigated. In addition, elemental analysis, IR spectra, and thermogravimetric analysis of these compounds are also described. © 2012 American Chemical Society.


He S.,CAS Changchun Institute of Applied Chemistry | He S.,University of Chinese Academy of Sciences | Hou H.,Jiangxi Normal University | Chen W.,CAS Changchun Institute of Applied Chemistry
Journal of Power Sources | Year: 2015

3D porous and self-supported carbon hybrids are promising electrode materials for supercapacitor application attributed to their prominent properties such as binder-free electrode fabrication process, excellent electric conductivity and high power density etc. We present here a facile chemical vapor deposition method to fabricate a novel 3D flexible carbon hybrid nanostructure by growing a monolayer of nitrogen-doped carbon nanotubes on the skeleton of carbon foam (N-CNTs/CF) with Fe nanoparticle as catalyst. With such 3D porous, flexible and ultralight carbon nanostructure as binder-free electrode material, large surface area is available and fast ionic transport is facilitated. Moreover, the carbon-based network can provide excellent electronic conductivity. The electrochemical studies demonstrate that the supercapacitor constructed from the N-CNTs/CF hybrid exhibit high power density of 69.3 kW kg-1 and good stability with capacitance retention ration above 95% after cycled at 50 A g-1 for 5000 cycles. Therefore, the prepared porous N-CNTs/CF nanostructure is expected to be a type of excellent electrode material for electrical double layer capacitors. © 2015 Elsevier B.V. All rights reserved.


Hu Y.,Colorado State University | Miyake G.M.,Colorado State University | Wang B.,CAS Changchun Institute of Applied Chemistry | Cui D.,CAS Changchun Institute of Applied Chemistry | Chen E.Y.-X.,Colorado State University
Chemistry - A European Journal | Year: 2012

Two ansa-half-sandwich rare-earth-metal (REM) dialkyl complexes supported by an ethylene-bridged fluorenyl (Flu)-N-heterocyclic carbene (NHC) ligand, [M{C 2H 4(η 5-Flu-κ 1-NHC)} (CH 2SiMe 3) 2] (M=Y, 1; Lu, 2), and a chiral ansa-sandwich samarocene incorporating a C 2 ligand, [Sm(η 5-C 12H 8) 2(thf) 2] (3), have been investigated for the coordination-addition polymerization of renewable methylene butyrolactones, α-methylene-γ- butyrolactone (MBL) and γ-methyl-α-methylene-γ-butyrolactone ( γMMBL). Both ansa-half-sandwich complexes 1 and 2 exhibit exceptional activity for the polymerization of γMMBL at room temperature in dimethylformamide (DMF); with a 0.25 mol % catalyst loading, quantitative monomer conversion can be achieved under 1 min, giving a high turn-over frequency (TOF) of 24 000 h -1. This TOF value represents a rate enhancement, by a factor of 8, 22, or 2400, over the polymerizations by unbridged samarocene [Sm(Cp*) 2(thf) 2] (Cp*=η 5-pentamethylcyclopentadienyl), by bridged ansa-samarocene 3 with C 2 ligation, or by the corresponding REM trialkyls without the ansa-Flu-NHC ligation, respectively. Complexes 1 and 2 are also highly active for the polymerization of β-methyl-α-methylene- γ-butyrolactone ( βMMBL), realizing the first example of the metal-mediated coordination polymerization of this monomer and its copolymerization with γMMBL. More remarkably, the resulting P βMMBL homopolymer is highly stereoregular (91 % mm) and exhibits a high T g of 290 °C. In sharp contrast, catalysts 1 and 2 have poor activity and efficiency in the polymerization of the parent MBL or the acyclic analog methyl methacrylate. Polymerization and kinetic studies using the most active catalyst (1) of the series have uncovered characteristics of its γMMBL polymerization and yielded a unimolecular propagation mechanism. A surprising chain-initiation pathway for the polymerization in DMF by 1 has been revealed, and catalytic polymerization in the presence of an organoacid has also been examined. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Mu H.,CAS Changchun Institute of Applied Chemistry | Pan L.,Tianjin University | Song D.,University of Massachusetts Amherst | Li Y.,CAS Changchun Institute of Applied Chemistry | Li Y.,Tianjin University
Chemical Reviews | Year: 2015

A study is conducted to investigate relationships between catalyst structures and catalytic properties during the use of neutral nickel catalysts for olefin homo- and copolymerization. Extensive investigations on neutral nickel catalysts have been conducted. Research has mainly focused on salicylaldimine frameworks due to their amenability to structural modifications. These novel catalysts have been used in olefin polymerization and copolymerization under various conditions. Studies have also been carried out on the functions of the additional stabilizing ligands and the electronic or steric effects of substituents.


Chen L.,CAS Changchun Institute of Applied Chemistry | Zhao X.,CAS Changchun Institute of Applied Chemistry | Lin Y.,CAS Changchun Institute of Applied Chemistry | Huang Y.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Chemical Communications | Year: 2013

Using a one-pot approach driven by the supramolecular interaction between β-cyclodextrin and adamantyl moieties, multifunctional viral nanoparticles can be facilely formulated for biomedical applications. © The Royal Society of Chemistry 2013.


Liu Y.,Max Planck Institute of Colloids and Interfaces | Liu Y.,CAS Changchun Institute of Applied Chemistry | Lipowsky R.,Max Planck Institute of Colloids and Interfaces | Dimova R.,Max Planck Institute of Colloids and Interfaces
Langmuir | Year: 2012

We studied the interfacial tension between coexisting phases of aqueous solutions of dextran and polyethylene glycol. First, we characterized the phase diagram of the system and located the binodal. Second, the tie lines between the coexisting phases were determined using a method that only requires measuring the density of the coexisting phases. The interfacial tension was then measured by a spinning drop tensiometer over a broad range of polymer concentrations close to and above the critical point. In this range, the interfacial tension increases by 4 orders of magnitude with increasing polymer concentration. The scaling exponents of the interfacial tension, the correlation length, and order parameters were evaluated and showed a crossover behavior depending on the distance to the critical concentration. The scaling exponent of the interfacial tension attains the value 1.50 ± 0.01 further away from the critical point, in good agreement with mean field theory, but the increased value 1.67 ± 0.10 closer to this point, which disagrees with the Ising value 1.26. We discuss possible reasons for this discrepancy. The composition and density differences between the two coexisting phases, which may be taken as two possible order parameters, showed the expected crossover from mean field behavior to Ising model behavior as the critical point is approached. The crossover behavior of aqueous two-phase polymer solutions with increasing concentration is similar to that of polymer solutions undergoing phase separation induced by lowering the temperature. © 2012 American Chemical Society.


Guo S.,CAS Changchun Institute of Applied Chemistry | Guo S.,University of Chinese Academy of Sciences | Guo S.,Brown University | Dong S.,CAS Changchun Institute of Applied Chemistry | Dong S.,University of Chinese Academy of Sciences
Journal of Materials Chemistry | Year: 2011

Graphene, a new material for which the Noble prize was won, has received increasing attention due to its unique physicochemical properties, such as a high surface area, excellent conductivity, a high mechanical strength, and good biocompatibility. In particular, in the last two years there has been explosive growth in studies relating to the use of graphene and its derivatives as enhanced materials or carriers for probes and recognition elements in the development of high-performance analytical devices. In this feature article, we will highlight recent important progress in the construction of graphene and its derivative-based high-performance analytical sensors. First, recent research efforts on the design of new electrochemical sensors, including amperometry, electrochemical luminescence (ECL), field-effect transistor (FET), electrochemical impedance, photoelectrochemical and surface plasmon resonance (SPR) electrochemical sensors are described. Then, we will move on to discuss more modish optical sensors, such as fluorescent, colorimetric and surface enhanced Raman spectroscopy (SERS) sensors. Finally, we conclude with a look at the future challenges and prospects of graphene and its derivative-related analytical devices. © 2011 The Royal Society of Chemistry.


Guo S.,CAS Changchun Institute of Applied Chemistry | Guo S.,University of Chinese Academy of Sciences | Guo S.,Brown University | Wang E.,CAS Changchun Institute of Applied Chemistry | Wang E.,University of Chinese Academy of Sciences
Nano Today | Year: 2011

Nobel metal nanomaterials (NMNs) with interesting physical and chemical properties are ideal building blocks for engineering and tailoring nanoscale structures for specific technological applications. Particularly, effectively controlling the size, shape, architecture, composition, hybrid and microstructure of NMNs plays an important role on revealing their new or enhanced functions and application potentials such as fuel cell and analytical sensors. This review article focuses on recent advances on controllable synthesis and fuel cell and sensing applications of NMNs. First, recent contributions on developing a wet-chemical approach for the controllable synthesis of noble metal nanomaterials with a rich variety of shapes, e.g. single-component Pt, Pd, Ag and Au nanomaterials, multi-component core/shell, intermetallic or alloyed nanomaterials, metal fluorescent nanoclusters and metal nanoparticles-based hybrid nanomaterials, are summarized. Then diversified approaches to different types of NMNs-based nanoelectrocatalysts with the aim to enhance their activity and durability for fuel cell reactions are outlined. The review next introduces some exciting push in the use of NMNs as enhanced materials or reporters or labels for developing new analytical sensors including electrochemical, colorimetric and fluorescent sensors. Finally, we conclude with a look at the future challenges and prospects of the development of NMNs. © 2011 Elsevier Ltd. All rights reserved.


Guo Z.,CAS Changchun Institute of Applied Chemistry | Guo Z.,Yanbian University | Ren J.,CAS Changchun Institute of Applied Chemistry | Wang J.,CAS Changchun Institute of Applied Chemistry | Wang E.,CAS Changchun Institute of Applied Chemistry
Talanta | Year: 2011

Ochratoxin A, a toxin produced by Aspergillus ochraceus and Penicillium verrucosum, is one of the most abundant food-contaminating mycotoxins in the world. It has been classified by the International Agency for Research on Cancer (IARC) as a possible human carcinogen. In this paper, a sensitive and selective fluorescent aptasensor for ochratoxin A (OTA) detection was constructed, utilizing single-walled carbon nanotubes (SWNTs) as quencher which can quench the fluorescence of free unfolded toxin-specific aptamer attached with FAM (carboxyfluorescein). Without any coating materials as compared to graphene-oxide based sensor, we obtained the detection limit of our sensing platform based on SWNTs to be 24.1 nM with a linear detection range from 25 nM to 200 nM. This technique responded specifically to OTA without interference from other analogues (N-acetyl-l-phenylalanine, warfarin and OTB). It has also been verified for real sample application by testing 1% beer containing buffer solution spiked with a series of concentration of OTA. © 2011 Elsevier B.V. All rights reserved.


Qian Q.,Renmin University of China | Huang X.,Renmin University of China | Zhang X.,Renmin University of China | Xie Z.,CAS Changchun Institute of Applied Chemistry | Wang Y.,Renmin University of China
Angewandte Chemie - International Edition | Year: 2013

Taking advantage of photothermal conversion, the surface pores of water-dispersible single-walled carbon nanotubes assembled on polymer particles were rapidly closed by NIR irradiation to produce macroporous polymeric microspheres with multiple interconnected chambers. These particles can act as smart containers to encapsulate and hold DNA molecules. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gao S.,Henan Normal University | Geng K.,Henan Normal University | Liu H.,Henan Normal University | Wei X.,Henan Normal University | And 3 more authors.
Energy and Environmental Science | Year: 2015

We present a cost-effective approach to dispose of amaranthus waste (the discarded leaves and stalks of amaranthus and the extract remains of natural amaranthus red) to yield nitrogen-doped carbon. Amaranthus waste is a natural, abundantly available, and yearly renewable source, acting as a single precursor for nitrogen (mainly from the lysine-rich amino acids) as well as carbon. It therefore eliminates the need for multiple hazardous chemicals including organic precursors for similar synthesis processes. Our facile experimental strategy without any activation supports reasonable nitrogen doping in porous carbon along with a high surface area and excellent conductivity, which leads to a superior electrocatalytic oxygen reduction activity and proves to be a promising alternative for costly Pt-based electrocatalysts in fuel cells in terms of excellent electrocatalytic performance, high selectivity, and long durability. This judicious transformation of organic-rich waste not only addresses the disposal issue, but also generates valuable functional carbon materials from the discard. Our as-synthesized carbon will certainly be believed to be a trend setter and have greater economic ramifications by creating value-added materials from waste. © 2015 The Royal Society of Chemistry.


Li M.,Changchun University of Technology | Sun G.,Changchun University of Technology | Yin P.,Changchun University of Technology | Ruan C.,CAS Changchun Institute of Applied Chemistry | Ai K.,CAS Changchun Institute of Applied Chemistry
ACS Applied Materials and Interfaces | Year: 2013

Vanadium pentoxide (V2O5) has attracted much attention for energy storage application because of its high Faradaic activity and stable crystal structure, which make it a promising electrode material for supercapacitors. However, the low electronic conductivity and small lithium-ion diffusion coefficient of V2O5 limit its practical applications. To overcome these limitations, a facile and efficient method is here demonstrated for the fabrication of V2O5/reduced graphene oxide (rGO) nanocomposites as electrode materials for supercapacitors. With this method, the reduction of graphene oxide can be achieved in a cost-effective and environmentally friendly solvent, without the addition of any other toxic reducing agent. Importantly, this solvent can control the formation of the uniform rodlike V2O5 nanocrystals on the surface of rGO. Compared to pure V2O5 microspheres, the V 2O5/rGO nanocomposites exhibited a higher specific capacitance of 537 F g-1 at a current density of 1 A g-1 in neutral aqueous electrolytes, a higher energy density of 74.58 Wh kg -1 at a power density of 500 W kg-1, and better stability even after 1000 charge/discharge cycles. Their excellent performances can be attributed to the synergistic effect of rGO and rodlike V2O 5 nanocrystals. Such impressive results may promote new opportunities for these electrode materials in high-energy-density storage systems. © 2013 American Chemical Society.


Shan Y.,CAS Changchun Institute of Applied Chemistry | Shan Y.,Changchun University of Technology | Wang H.,CAS Changchun Institute of Applied Chemistry | Wang H.,University of Chinese Academy of Sciences
Chemical Society Reviews | Year: 2015

The cell membrane is one of the most complicated biological complexes, and long-term fierce debates regarding the cell membrane persist because of technical hurdles. With the rapid development of nanotechnology and single-molecule techniques, our understanding of cell membranes has substantially increased. Atomic force microscopy (AFM) has provided several unprecedented advances (e.g., high resolution, three-dimensional and in situ measurements) in the study of cell membranes and has been used to systematically dissect the membrane structure in situ from both sides of membranes; as a result, novel models of cell membranes have recently been proposed. This review summarizes the new progress regarding membrane structure using in situ AFM and single-molecule force spectroscopy (SMFS), which may shed light on the study of the structure and functions of cell membranes. © The Royal Society of Chemistry 2015.


Yuan F.-Q.,CAS Changchun Institute of Applied Chemistry | Yuan F.-Q.,University of Chinese Academy of Sciences | Han F.-S.,CAS Changchun Institute of Applied Chemistry | Han F.-S.,Dalian University of Technology
Advanced Synthesis and Catalysis | Year: 2013

A one-pot cascade reaction for the synthesis of polysubstituted benzofurans and naphthopyrans from simple phenols and propargylic alcohols catalyzed by iron(III) is presented. The results demonstrate that the structural specificity for the formation of furan and pyran products is controlled by the structural nature of the propargylic alcohols. Namely, benzofurans could be synthesized efficiently from phenols and secondary propargylic alcohols in the presence of 5 mol% of iron(III) chloride hexahydrate (FeCl3·6H 2O) catalyst. On the other hand, pyran derivatives were obtained exclusively when tertiary propargylic alcohols were employed. Mechanistic studies revealed that presumably due to the discriminated steric effect of secondary and tertiary propargylic alcohols, the Fe-catalyzed Friedel-Crafts (F-C) reaction of phenols with the two types of alcohols proceeds via different models. Most importantly, we have demonstrated for the first time that fully 2,3,4-substituted naphthopyrans could be synthesized efficiently via the iron-catalyzed one-pot cascade reaction. Consequently, the results presented herein provide straightforward pathways for versatile syntheses of valuable benzofuran and pyran derivatives from simple phenolic compounds and propargylic alcohols. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gong D.,Ningbo University | Wang B.,CAS Changchun Institute of Applied Chemistry | Jia X.,Chinese Institute of Urban Environment | Zhang X.,CAS Changchun Institute of Applied Chemistry
Dalton Transactions | Year: 2014

A family of cobalt complexes supported by a tridentate Schiff base ligand with a labile donor (O, S, N) as a pendant arm (Co1-Co12, formulated as CoL 2) were synthesized by the treatment of the corresponding ligands with cobalt acetate tetrahydrate. The resultant complexes were well characterized by elemental analysis, FT-IR, magnetic moment as well as EI-MS. The solid-state structures of Co7 and Co12 were determined by X-ray diffraction and both established a distorted octahedron geometry around the cobalt center. The butadiene polymerization capabilities of the 12 complexes were evaluated and compared in representative cases. Diethylaluminum chloride (AlEt2Cl) was found to be the compatible activator resulting in highly active catalysts for producing polybutadiene of 93.8-98.2% cis-1,4 enchainment with negligible 1,2-structure and trans-1,4 units. It appears that a certain degree of lability of the donor is beneficial for high catalytic activity, generally following the order of O > S > N, and the high cis-1,4 selectivity. Moreover, the remarkable thermal stability of these systems has been achieved: the catalytic systems have the ability of conducting a high level of active and selective polymerization, reaching an upper limit of polymerization temperature of about 70 °C. The enhanced catalytic performances were further rationalized by the established diene polymerization mechanism, which could shed light on developing highly selective and reactive industrially applicable catalysts with an enhanced thermal stability. © 2014 The Royal Society of Chemistry.


Wang L.,CAS Changchun Institute of Applied Chemistry | Cui D.,CAS Changchun Institute of Applied Chemistry | Hou Z.,RIKEN | Li W.,Dalian University of Technology | Li Y.,Dalian University of Technology
Organometallics | Year: 2011

Bis(phosphino)carbazole, HL (HL = 3,6-(tBu)2-1,8-(PPh 2)2-carbazole), reacted with rare-earth-metal tris(aminobenzyl) complexes (Ln(CH2C6H4N(Me) 2-o)3) to afford the first PNP-carbazolide rare-earth-metal bis(alkyl) complexes, LLn(C6H4CH 2N(Me)2)2 (Ln=Y (1), Sc (2), Er (3)). The yttrium complex 1 was characterized by X-ray diffraction analysis as a solvent-free monomer, in which the carbazolide ligand coordinates to the Y 3+ ion in a κP:κN:κP′-tridentate mode and the two aminobenzyl groups coordinate to the Y3+ ion in η1C:κN-bidentate modes. Complexes 1-3 combined with [Ph3C][B(C6F5)4] gave cationic catalyst systems that initiated cis-1,4-polymerizations of 1,3-conjugated dienes with high activities. Especially, the system 1/[Ph3C][B(C 6F5)4] displayed excellent cis-1,4-selectivity (>99%) and living mode at a broad range of polymerization temperatures (0-80 °C). Remarkably, the living yttrium-polydiene active species could further initiate the ring-opening polymerization of ε-caprolactone to give selectively poly(cis-1,4-diene)-b-polycaprolactone block copolymer with controllable molecular weight (Mn = (10-70) - 104) and narrow polydispersity (PDI = 1.15-1.47). © 2011 American Chemical Society.


Yang J.,Southwest University | Lin J.,CAS Changchun Institute of Applied Chemistry
Journal of the Electrochemical Society | Year: 2010

Lu2 O3: Yb3+ / Ho3+ phosphors were prepared by a Pechini sol-gel process. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), cathodoluminescence (CL) spectra, as well as lifetimes were utilized to characterize the synthesized phosphors. XRD and HRTEM results reveal that the samples are obtained with high crystallinity. The FESEM images indicate that Lu2 O3: Yb3+ / Ho3+ phosphors are composed of fine and spherical grains around 50-80 nm in size. Under the excitation of UV light, 980-nm laser, and low-voltage electron beams, all Lu2 O3: Yb3+ / Ho3+ phosphors show the characteristic emission of the Ho3+ ion (F45, S25 → I85 transition) with green luminescence, which is easily observed by our naked eyes. The corresponding luminescent mechanisms have been discussed. Due to the excellent PL (including upconversion and downconversion) properties, CL properties, and cheap materials of the Lu2 O3: Yb3+ / Ho3+ phosphors, the as-prepared phosphors are potentially applied for fluorescent lamps, upconversion fluorescent labels, and field emission display devices. © 2010 The Electrochemical Society.


Shang X.,Changchun University of Technology | Han D.,Changchun University of Science and Technology | Li D.,Changchun University of Technology | Wu Z.,CAS Changchun Institute of Applied Chemistry
Chemical Physics Letters | Year: 2013

We report a quantum-chemistry analysis of four heteroleptic iridium(III) complexes (tfmppy)2Ir(tpip) [tfmppy = 4- trifluoromethylphenylpyridine, tpip = tetraphenylimido-diphosphinate] (1), (tfmpyN3)2Ir(tpip) [tfmpyN3 = 4-trifluoromethylphenyl-[1,2,3]-triazole] (2), (CN-pyN3) 2Ir(tpip) [CN-pyN3 = 4-cyanophenyl-[1,2,3]-triazole] (3) (ph-pta)2Ir(tpip) [ph-pta = 2-(5-phenyl-[1,2,4]-triazol-3-yl)- pyridine] (4), which have been studied by using density functional theory (DFT) and time-dependent DFT (TDDFT) methods, to investigate their electronic structures, injection and transport properties, absorption and phosphorescence mechanism. The results reveal the different cyclometalated ligands have a large impact on the charge transfer performances of the studied complexes. The complex 4 possess better charge transfer abilities and balanced charge transfer rates, which is a potential candidate as blue-emitting material. © 2013 Elsevier B.V. All rights reserved.


Chen K.,CAS Changchun Institute of Applied Chemistry | Chen K.,Dalian University of Technology | Dong Noh Y.,Pennsylvania State University | Li K.,Dalian University of Technology | And 3 more authors.
Journal of Physical Chemistry C | Year: 2013

We report a coupled microwave-hydrothermal process to crystallize polymorphs of MnO2 such as α-, β-, and γ-phase samples with plate-, rod-, and wirelike shapes, by a controllable redox reaction in MnCl2-KMnO4 aqueous solution system. MnCl 2-KMnO4 redox reaction system was for the first time applied to MnO2 samples under the coupled microwave-hydrothermal conditions, which shows clear advantages such as shorter reaction time, well-crystallized polymorphic MnO2, and good electrochemical performances as electrode materials for lithium ion batteries. For comparison, we also did separate reactions with hydrothermal only and microwave only in our designed MnCl2-KMnO4 aqueous system. The present results indicate that MnCl2-KMnO4 reaction system can selectively lead to α-, β-, and γ-phase MnO2, and the as-crystallized MnO2 samples can show interesting electrochemical performances for both lithium-ion batteries and supercapacitors. Electrochemical measurements show that the as-crystallized MnO2 supercapacitors have Faradaic reactivity sequence α- > γ- > β-MnO2 upon their tunnel structures, the intercalation-deintercalation reactivity of these MnO2 cathodes follows the order γ- > α- > β-phase, and the conversion reactivity of these MnO2 anodes follows the order γ- > α- > β-phase. MnCl 2-KMnO4 reaction system can also lead to the mixed-phase MnO2 (β- and γ-MnO2), which can provide better anode performances for lithium-ion batteries. The current work deepens the fundamental understanding of several aspects of physical chemistry, for example, the chemical reaction controllable synthesis, crystal structure selection, electrochemical property improvement, and electrochemical reactivity, as well as their correlations. © 2013 American Chemical Society.


Sun C.,CAS Changchun Institute of Applied Chemistry | Sun C.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology
Journal of Physical Chemistry C | Year: 2013

A quantitative relationship between bond length, crystal morphology, and particle size has been established to investigate the morphology transformation of ZnO nanostructures at the nanoregime. Surface bonding conditions dominate the anisotropic growth of ZnO nanoparticles. Critical surface bond lengths at which ZnO can respectively exhibit pyramid-, truncated pencil-, pencil-, and rod-like morphologies were quantitatively calculated under different extension/shrinkage degrees of Zn-O bond length in the lattice. The size of particular ZnO nanostructures was obtained by tracking the variation of bond length in the lattice. At the nanoregime, ZnO thermodynamically prefers to exhibit nanorods with a diameter smaller than 3.60 nm, nanopyramids with size smaller than 2.94 nm, nanopencils with a diameter larger than 3.15 nm, and truncated nanopencils with a diameter larger than 3.92 nm. Our results are in agreement with experimental observations and indicate the fundamental role of surface bonding control in tailoring anisotropic growth of ZnO nanostructures. © 2013 American Chemical Society.


Chen G.-J.,CAS Changchun Institute of Applied Chemistry | Han F.-S.,CAS Changchun Institute of Applied Chemistry | Han F.-S.,Dalian University of Technology
European Journal of Organic Chemistry | Year: 2012

The Suzuki-Miyaura cross-coupling of aryl sulfamates and boronic acids was investigated by using [1,3-bis(diphenylphosphanyl)propane]nickel(II) chloride {NiCl 2(dppp)} as the catalyst. The results showed that NiCl 2(dppp) is a highly active and general catalyst that allows effective Suzuki-Miyaura cross-coupling of aryl sulfamates with a slight excess amount of the boronic acid (1.2 equiv.) in the presence of a low catalyst loading (generally 1.0-1.5 mol-%). The method also displays broad generality not only to various aryl sulfamates, but also to an array of boronic acids. Furthermore, various functional groups are tolerated. These apparent advantages make NiCl 2(dppp) a practical and reliable catalyst system for the Suzuki-Miyaura coupling of aryl sulfamates. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Guo Y.,Shanxi University | Guo Y.,CAS Changchun Institute of Applied Chemistry | Li J.,CAS Changchun Institute of Applied Chemistry | Dong S.,CAS Changchun Institute of Applied Chemistry
Sensors and Actuators, B: Chemical | Year: 2011

In this paper, we present dual biosensor platforms based on hemin functionalized graphene nanosheets (H-GNs). The nanomaterial combines the features of both graphene (high conductivity and surface area) and hemin (excellent catalysis and intrinsic peroxidase-like activity). It not only shows excellent electrocatalysis of the reduction of H2O2 but also exhibits intrinsic peroxidase-like activity that can catalyze H 2O2 to oxidize 3,3,5,5-tetramethylbenzidine (TMB) to produce a blue color reaction. Based on these properties, the simple, economical, and highly sensitive amperometric and colorimetric biosensors for H2O2 and glucose have been developed. The linear relationships for H2O2 and glucose were obtained from 0.5 μM to 0.4 mM and 0.05 μM to 0.5 mM by amperometric and colorimetric methods, respectively. The detection limits for H2O2 and glucose reached to 0.2 μM and 0.3 μM by amperometric method. By colorimetric methods, the detection limits for H2O2 and glucose were as low as 20 nM and 30 nM, respectively. The rapid, simple and sensitive sensing platform showed great promising applications in the pharmaceutical, clinical and industrial detection of H2O2 and glucose. © 2011 Elsevier B.V. All rights reserved.


Chen K.,Dalian University of Technology | Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
Physical Chemistry Chemical Physics | Year: 2013

We reported a chemical reaction controlled mechanochemical route to synthesize mass CuO nanosheets by manual grinding in a mortar and pestle, which does not require any solvent, complex apparatus and techniques. The activation of chemical reactions by milling reactants was thus proved, and the energy from mechanical grinding promotes the fast formation of CuO nanoribbons. The resultant materials have preferential nanoscale ribbon-like morphology that can show large capacity and high cycle performance as lithium-ion battery anodes. After 50 cycles, the discharge capacity of CuO nanoribbon electrodes is 614.0 mA h g-1, with 93% retention of the reversible capacity. The thermodynamic reactions of the CuO battery showed size-dependent characterization. The microstructures of CuO nanosheets and reaction routes can be controlled by the ratio of NaOH/CuAc2 according to the chemical reactions involved. The intact nanoribbon structure, thin-layer, and hierarchical structures endow present CuO materials with high reversible capacity and excellent cycling performances. The simple, economical, and environmentally friendly mechanochemical route is of great interest in modern synthetic chemistry. © 2013 The Owner Societies.


Han F.-S.,CAS Changchun Institute of Applied Chemistry | Han F.-S.,Dalian University of Technology
Chemical Society Reviews | Year: 2013

In the transition-metal-catalyzed cross-coupling reactions, the use of the first row transition metals as catalysts is much more appealing than the precious metals owing to the apparent advantages such as cheapness and earth abundance. Within the last two decades, particularly the last five years, explosive interests have been focused on the nickel-catalyzed Suzuki-Miyaura reactions. This has greatly advanced the chemistry of transition-metal-catalyzed cross-coupling reactions. Most notably, a broad range of aryl electrophiles such as phenols, aryl ethers, esters, carbonates, carbamates, sulfamates, phosphates, phosphoramides, phosphonium salts, and fluorides, as well as various alkyl electrophiles, which are conventionally challenging, by applying palladium catalysts can now be coupled efficiently with boron reagents in the presence of nickel catalysts. In this review, we would like to summarize the progress in this reaction. © 2013 The Royal Society of Chemistry.


Guo Y.,CAS Changchun Institute of Applied Chemistry | Guo Y.,Shanxi University | Guo S.,CAS Changchun Institute of Applied Chemistry | Fang Y.,CAS Changchun Institute of Applied Chemistry | Dong S.,CAS Changchun Institute of Applied Chemistry
Electrochimica Acta | Year: 2010

In this work, a highly sensitive electrochemical sensor for the determination of tryptophan (Trp) was fabricate by electrodeposition of gold nanoparticles (AuNPs) onto carbon nanotube (CNT) films pre-cast on a glassy carbon electrode (GCE), forming an AuNP-CNT composite-modified GCE (AuNP-CNT/GCE). Scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used for the surface analysis of the electrode. The results indicate that the hybrid nanomaterials induced a substantial decrease in the overpotential of the Trp oxidation reaction and exhibited a remarkable synergistic effect on the electrocatalytic activity toward the oxidation of Trp. In phosphate buffer solution (pH 7.4), the modified electrode showed excellent analytical performance for the amperometric determination of Trp. The peak currents possess a linear relationship with the concentration of Trp in the range of 30 nM to 2.5 μM, and the detection limit is 10 nM (S/N = 3). In addition, the modified electrode was used to determine Trp concentration in pharmaceutical samples with satisfactory results. © 2010 Elsevier Ltd. All rights reserved.


Huang S.,CAS Changchun Institute of Applied Chemistry | Jiang S.,Tianjin University
RSC Advances | Year: 2014

Biocompatible and biodegradable block copolymers (BBCPs) have become increasingly important in polymer science, and have many potential applications in polymer materials. The structures of BBCPs, which are determined by the competition between crystallization, microphase separation, kinetics and processing, have a tremendous influence on the final properties and applications. In this review, the most recent advances are highlighted in the crystalline structures and morphologies of BBCPs with at least one crystalline block. Particular emphasis is placed on the influences of chemical composition, molecular architecture, crystallization pathway, and film thickness on the structures and morphologies of the block copolymers. The formation and the characteristics of the structures grown in the block copolymers are helpful for understanding the interplay between crystallization and phase segregation, morphologies, structural evolution and their applications. © 2014 the Partner Organisations.


Sun L.,Changchun University of Technology | Zhao Z.,Changchun University of Science and Technology | Zhou Y.,CAS Changchun Institute of Applied Chemistry | Liu L.,Changchun University of Technology
Nanoscale | Year: 2012

Owing to their extensive practical applications and fundamental importance, the controllable synthesis of well-faceted anatase TiO 2 crystal with high percentage of reactive facets has attracted increasing attention. Here, nano-sized anatase TiO 2 sheets mainly dominated by {001} facets had been prepared on graphene sheets by using a facile solvothermal synthetic route. The percentage of {001} facets in TiO 2 nanosheets was calculated to be ca. 64%. The morphologies, structural properties, growth procedures and photocatalytic activities of the resultant TiO 2/graphene nanocomposites were investigated. In comparison with commercial P25 and pure TiO 2 nanosheets, the composite exhibited significant improvement in photocatalytic degradation of the azo dye Rhodamine B under visible light irradiation. The enhancement of photocatalytic activity and stability was attributed to the effective charge anti-recombination of graphene and the high catalytic activity of {001} facets. © 2012 The Royal Society of Chemistry.


Li K.,Dalian University of Technology | Yang P.,Dalian University of Technology | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
Acta Materialia | Year: 2012

We have presented an efficient method to predict the anisotropic hardness of crystalline materials along different crystallographic directions or on different crystallographic planes in terms of electronegativity. Bond stretching and bending strengths, respectively, are proposed to characterize the ability of a chemical bond to resist stretching and bending deformation, which are the main microscopic deformations in single crystals when measuring indentation hardness. Good agreement between the calculated and experimental values of anisotropic hardness for a large range of crystalline materials has been achieved, including sphalerite, wurtzite and rocksalt structured materials, as well as oxides (e.g. α-SiO2 and LaGaO3) and graphite. The anisotropic hardness values of other important materials, such as B12 analogs, group IVA nitrides, tungsten carbide structured materials, and transition metal di- and tetra-borides, were quantitatively predicted. We found that materials with the same crystal structure have the same or similar hardness anisotropy. Furthermore, the more orderly bond arrangement in single crystals and the greater bond ionicity often result in greater hardness anisotropy. This work shines a light on the nature of hardness and on studies of the anisotropy of other macroscopic properties of crystalline materials. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.


Zhao Y.-L.,CAS Changchun Institute of Applied Chemistry | Zhao Y.-L.,Northeast Normal University | Wu G.-J.,Northeast Normal University | Li Y.,CAS Changchun Institute of Applied Chemistry | And 3 more authors.
Chemistry - A European Journal | Year: 2012

We present a general approach to C-P bond formation through the cross-coupling of aryl halides with a dialkyl phosphite, diphenylphosphine oxide, and diphenylphosphane by using [NiCl 2(dppp)] as catalyst (dppp=1,3-bis(diphenylphosphino)propane). This catalyst system displays a broad applicability that is capable of catalyzing the cross-coupling of aryl bromides, particularly a range of unreactive aryl chlorides, with various types of phosphorus substrates, such as a dialkyl phosphite, diphenylphosphine oxide, and diphenylphosphane. Consequently, the synthesis of valuable phosphonates, phosphine oxides, and phosphanes can be achieved with one catalyst system. Moreover, the reaction proceeds not only at a much lower temperature (100-120 °C) relative to the classic Arbuzov reaction (ca. 160-220 °C), but also without the need of external reductants and supporting ligands. In addition, owing to the relatively mild reaction conditions, a range of labile groups, such as ether, ester, ketone, and cyano groups, are tolerated. Finally, a brief mechanistic study revealed that by using [NiCl 2(dppp)] as a catalyst, the Ni II center could be readily reduced in situ to Ni 0 by the phosphorus substrates due to the influence of the dppp ligand, thereby facilitating the oxidative addition of aryl halides to a Ni 0 center. This step is the key to bringing the reaction into the catalytic cycle. Making bonds: C-P bonds were formed by the Ni-catalyzed cross-coupling of aryl halides and phosphorus substrates without the need of external reductants. Aryl bromides and less reactive aryl chlorides underwent smooth coupling with several different phosphorus substrates to afford phosphonates, phosphine oxides, and phosphines (see scheme; dppp=1,3-bis(diphenylphosphino)propane). Due to the mild reaction conditions, a range of labile groups, such as ether, ester, ketone, and cyano groups, are tolerated. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang Y.,Dalian University of Technology | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
Functional Materials Letters | Year: 2012

α-MnO2 electrode materials with sphere-, rod- and flower-like nanostructures were for the first time fabricated by a redox reaction between KMnO4 and NaHSO3 in chemical bath. Crystal structure and morphology of the as-crystallized samples were characterized by X-ray diffraction and scanning electron microscopy. The influence of reaction temperature and H+ concentration on both morphology and crystalline nature was investigated. Their electrochemical behaviors were investigated by cycling voltammetry and galvanostatic charge/discharge measurements in a three-electrode glass cell. Depending upon different synthesis conditions of α-MnO2 electrodes, their specific capacitance values varied in the range of 43 to 197 F g-1 at the current density of 1 A g-1. Moreover, their specific capacitance values decrease with increasing crystallinity and particle size. In this work, we conclude that the energy storage mechanism is closely related to the particle aggregation state of electrode materials. © 2012 World Scientific Publishing Company.


Chen K.,CAS Changchun Institute of Applied Chemistry | Chen K.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology
CrystEngComm | Year: 2013

We present a chemoaffinity-mediated crystallization strategy to fabricate Cu2O with different morphologies for studying their electrochemical performances as lithium-ion battery anode materials. The chemical reaction routes were finely-designed by including important anions such as OH -, SO4 2-, NO3 -, Ac -, and Cl- in the redox system of N2H 4 and Cu2+. With different affinity abilities of the anions in terms of hard-soft acid-base theory, two growth mechanisms were evidenced, which can lead to the crystallization of spherical aggregations and octahedra, respectively. The crystallization of Cu2O octahedra occurred in the presence of OH-, which is independent of anions, due to the higher chemoaffinity of OH- with Cu2+. Without adding additional OH-, anions such as SO4 2-, NO3 -, Ac-, and Cl- can induce diverse chemical reactions to effectively control the growth of Cu2O spherical aggregations. Electrochemical measurements indicated that Cu 2O octahedra can show better cyclability than that of spherical aggregations. The present work validates that the chemoaffinity-mediated method is a useful bottom-up strategy to crystallize high performance anode materials. This journal is © The Royal Society of Chemistry.


Guan J.,CAS Changchun Institute of Applied Chemistry | Guan J.,University of Chinese Academy of Sciences | Wu G.-J.,Northeast Normal University | Han F.-S.,CAS Changchun Institute of Applied Chemistry | Han F.-S.,Dalian University of Technology
Chemistry - A European Journal | Year: 2014

A novel protocol for the Pd-catalyzed ortho-arylation of aryl phosphinamide with boronic acid is reported. By using phosphinamide as a new directing group, the reaction proceeds efficiently under mild conditions at 40 °C. Mechanistic studies reveal that the reaction proceeds via a PdII to Pd0 cycle. The phosphinamide group is also shown to be an effective orienting group for direct C-H amination. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Guo Y.,CAS Changchun Institute of Applied Chemistry | Guo Y.,University of Chinese Academy of Sciences | Guo Y.,Shanxi University | Guo S.,CAS Changchun Institute of Applied Chemistry | And 5 more authors.
ACS Nano | Year: 2010

Cyclodextrins (CDs) are oligosaccharides composed of six, seven, or eight glucose units (α-, β-, or γ-CD, respectively), which are toroidal in shape with a hydrophobic inner cavity and a hydrophilic exterior. These interesting characteristics can enable them to bind selectively various organic, inorganic and biological guest molecules into their cavities to form stable host - guest inclusion complexes or nanostructured supramolecular assemblies in their hydrophobic cavity. On the other hand graphene nanosheet (GN), a rising-star material, holds great promise for potential applications in many technological fields due to its high surface areas, low cost, and high conductivity. If GNs are modified with CDs, it is possible to obtain new materials simultaneously possessing unique properties of GNs and cyclodextrins through combining their individual obvious advantages. In this article, we demonstrate for the first time a simple wet-chemical strategy for the preparation of CD - graphene organic - inorganic hybrid nanosheets (CD - GNs), which exhibited high solubility and stability in polar solvent. The obtained CD - GNs were characterized by UV - vis spectroscopy, static contact angle measurement, thermogravimetric analysis, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, atomic force microscopy, transmission electron microscopy, and electrochemical impedance spectroscopy, which confirmed that CD had been effectively functionalized on the surface of GNs. Furthermore, the formation mechanism of CD - GNs was also discussed. Interestingly, GNs here could load a number of CD molecules, which was very important for greatly enhancing the supramolecular function of CDs. Electrochemical results obviously reveal that CD - graphene organic - inorganic hybrid nanosheets could exhibit very high supramolecular recognition and enrichment capability and show much higher electrochemical response toward eight probe molecules (biomolecules and drugs) than unmodified GNs and carbon nanotubes, which is probably caused by the synergetic effects from GNs (high conductivity and high surface area) and CD molecules (host - guest recognition and enrichment). © 2010 American Chemical Society.


Chen K.,Dalian University of Technology | Chen K.,CAS Changchun Institute of Applied Chemistry | Song S.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
CrystEngComm | Year: 2013

This paper describes a facile vapor-phase strategy for the crystallization of copper oxide on Cu foil substrate in air and the further fabrication of integrated Cu xO-Cu electrodes with Cu xO readily on the Cu foil current collector, without using conductive carbon and binder. The oxidation behavior of Cu foil in air was identified by XRD, SEM and electrochemical measurements. In the whole temperature range from 200 to 800 °C, Cu 2O is the dominant product of the as-oxidized Cu, and CuO is grown on the surface of the Cu 2O layer. The phase composition and thickness of oxidation products can be controlled by the reaction temperature and time. Both thermodynamic data and crystallography of the as-oxidized Cu products indicate that the Cu/Cu 2O/CuO tri-layered structures can be conveniently fabricated according to the oxidation sequence Cu → Cu 2O → CuO. The integrated Cu xO-Cu electrodes can show better cycling stability and higher capability than those Cu xO-C blend electrodes. The present work provides a new avenue for the large-scale configuration of integrated metal oxide materials as anode materials for lithium-ion batteries. This journal is © The Royal Society of Chemistry.


Xu H.,CAS Changchun Institute of Applied Chemistry | Liu P.-T.,Changchun University of Science and Technology | Li Y.-H.,Changchun University of Science and Technology | Han F.-S.,Dalian University of Technology
Organic Letters | Year: 2013

An unprecedented protocol for the copper-mediated direct cyanation of aryl C-H by employing 2,2′-azobisisobutyronitrile (AIBN) as a free radical "CN" source is presented. The protocol not only provides a more efficient pathway for the synthesis of aryl nitriles in terms of the yields and the loading amount of copper salts but also, more importantly, represents a novel strategy for aryl C-H cyanation via a CN free-radical mechanism as compared to the CN anion-participating protocols often reported. © 2013 American Chemical Society.


He W.,CAS Changchun Institute of Applied Chemistry | Jiang C.,CAS Changchun Institute of Applied Chemistry | Wang J.,Changchun University of Technology | Lu L.,CAS Changchun Institute of Applied Chemistry
Angewandte Chemie - International Edition | Year: 2014

Nitrogen-doped species (NDs) are theoretically accepted as a determinant of the catalytic activity of metal-free N-doped carbon (NC) catalysts for oxygen reduction reaction (ORR). However, direct relationships between ND type and ORR activity have been difficult to extract because the complexity of carbon matrix impairs efforts to expose specific NDs. Herein, we demonstrate the fabrication of a 3D hierarchically porous NC catalyst with micro-, meso-, and macroporosity in one structure, in which sufficient exposure and availability of inner-pore catalytic sites can be achieved due to its super-high surface area (2191 cm 2-g-1) and interconnected pore system. More importantly, in-situ formation of graphitic-N species (GNs) on the surface of NC stimulated by KOH activation enables us to experimentally reveal the catalytic nature of GNs for ORR, which is of great significance for the design and development of advanced metal-free NC electrocatalysts. Spotlighting nitrogen: Preferential exposure of graphitic-N species (GNs) on the surface of bi-continuous N-doped carbon (NC) films that feature hierarchically porous frameworks has been achieved. This unique design was used to identify the catalytic nature of GNs which paves the way to developing highly active metal-free NC electrocatalysts for oxygen reduction. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology
International Journal of Nanotechnology | Year: 2013

In this paper, we briefly review the recent research on crystallisation of cuprous oxide (Cu2O). Cu2O is an important semiconductor with cubic crystal structure and many applications in solar cell, catalysis, sensor, photonic crystals, etc. {100}, {111} and {110} surface structures of Cu2O are very important for controlling crystallisation. Different synthetic methods such as oxidation and reduction methods, together with different experimental parameters, size- and shape-controlled Cu2O crystals are summarised. The mechanisms underlying the crystallisation of Cu2O crystals are also highlighted. Our current work shows that Cu2O is a good model material to study crystallisation of inorganic materials. © 2013 Inderscience Enterprises Ltd. © 2013 Inderscience Enterprises Ltd.


Chen K.,Dalian University of Technology | Chen K.,CAS Changchun Institute of Applied Chemistry | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
CrystEngComm | Year: 2012

This work reports the chemical reaction-controlled crystallization of Cu 2O with systematic shape evolution from nanowires, through nanoparticle-aggregated spheres and octahedra to truncated octahedra and cuboctahedra by a two-step "precursor formation-crystallization" process. The results reveal that the shape, size, composition variation and overall reaction mechanism were mostly determined by the pH-dependent precursor species Cu 2(OH) 3NO 3, Cu(OH) 2 and Cu(OH) 4 2-. The addition of specific amounts of OH - to the solution is the key to adjusting the reduction and complexation reactions that control the crystallization of Cu 2O; high pH enhanced the reducing power of starch and the complexation ability of OH -. Cu 2O or Cu can be selectively crystallized under alkaline or acidic conditions due to the pH-dependence of the reduction reaction. The intriguing results show that the size of truncated octahedra first increases, then decreases with increasing pH owing to the competition between the complexation and redox reactions. The results demonstrate that control of pH-dependent chemical reactions is an effective way to adjust the crystallization of oxides and their electrochemical activity. © 2012 The Royal Society of Chemistry.


Zhang C.,CAS Changchun Institute of Applied Chemistry | Zhang C.,Dalian University of Technology | Li K.,Dalian University of Technology | Song S.,CAS Changchun Institute of Applied Chemistry | And 2 more authors.
Chemistry - A European Journal | Year: 2013

A facile and reversible phase-transfer protocol for luminescent ZnO quantum dots (QDs) between methanol and hexane is presented. Oleylamine together with acetic acid trigger this reversible phase-transfer process, during which the structure and optical properties of the ZnO QDs are well-protected. ZnO QDs with a diameter of approximately 5 nm emit yellow light at 525 nm, while those with a diameter of approximately 4 nm emit green light at 510 nm. The positions of the emission peaks remain unchanged during the presented phase-transfer process. The Pearson's hard and soft (Lewis) acid and base principle, together with the principle that similar substances are more likely to be dissolved by each other, describes the current reversible phase-transfer process. Herein, we circumvent the time-consuming work required to synthesize ZnO QDs in different environments, making it possible to combine the advantages of ZnO QDs dispersed in polar and nonpolar solvents. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhu J.,Dalian University of Technology | Xue D.,Dalian University of Technology | Xue D.,CAS Changchun Institute of Applied Chemistry
CrystEngComm | Year: 2014

We report an electrochemically modulated method for single crystal silver nanobelts with uniform thickness and width, which grow along the <110> direction with {111} facets. The procedure involves a crystallographically- oriented and interfacial kinetic controlled chemical reduction process by using a sacrificial cathode electrode with nanochannel templates. Silver nanobelt-bundle arrays are formed orientedly within nanochannels and can be easily dispersed into individual nanobelts by removing the template. These nanobelts exhibit two distinct surface plasmon resonances (SPR) at 456 and 980 nm, and show a strong spontaneous emission (SE) at 519 nm when excited by UV or blue light. These silver nanobelts with a quasi-two-dimensional planar nanostructure are an important material for surface plasmon resonance-based technology, which may open up many practical opportunities in the fields of optics, electronics and photoelectronics. © 2014 The Royal Society of Chemistry.


Du Z.-J.,CAS Changchun Institute of Applied Chemistry | Du Z.-J.,University of Chinese Academy of Sciences | Guan J.,CAS Changchun Institute of Applied Chemistry | Wu G.-J.,CAS Changchun Institute of Applied Chemistry | And 5 more authors.
Journal of the American Chemical Society | Year: 2015

We present the enantioselective synthesis of P-stereogenic phosphinamides through Pd-catalyzed desymmetric ortho C-H arylation of diarylphosphinamides with boronic esters. The method represents the first example of the synthesis of P-stereogenic phosphorus compounds via the desymmetric C-H functionalization strategy. The reaction proceeded efficiently with a wide array of reaction partners to afford the P-stereogenic phosphinamides in up to 74% yield and 98% ee. The efficiency was further demonstrated by gram scale syntheses. Moreover, the flexible conversion of the P-stereogenic phosphinamides into various types of P-stereogenic phosphorus derivatives was also elaborated. Thus, the protocol provides a novel tool for the efficient and versatile synthesis of P-stereogenic compounds. © 2015 American Chemical Society.


Dang S.,CAS Changchun Institute of Applied Chemistry | Zhang J.-H.,CAS Fujian Institute of Research on the Structure of Matter | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry | Sun Z.-M.,CAS Fujian Institute of Research on the Structure of Matter | Zhang H.,CAS Changchun Institute of Applied Chemistry
Chemical Communications | Year: 2012

A family of new luminescent lanthanide MOFs have been synthesized and display a strong second-harmonic generation response, which is 6.0 times that of KDP and phase matchable. The LnMOFs also exhibit typical luminescence emissions with high quantum yields (up to 70.0% for Tb). © 2012 The Royal Society of Chemistry.


Yi F.-Y.,CAS Changchun Institute of Applied Chemistry | Zhang J.,CAS Fujian Institute of Research on the Structure of Matter | Zhang H.-X.,CAS Fujian Institute of Research on the Structure of Matter | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry | Sun Z.-M.,CAS Fujian Institute of Research on the Structure of Matter
Chemical Communications | Year: 2012

A family of chiral porous metal-organic frameworks were synthesized through an unprecedented chiral transformation process only involving achiral components. This method may provide a new point of view to rationally design targeted chiral MOFs and may shed light on the symmetry breaking mechanism. © 2012 The Royal Society of Chemistry.


Jian Z.,CAS Changchun Institute of Applied Chemistry | Jian Z.,University of Chinese Academy of Sciences | Cui D.,CAS Changchun Institute of Applied Chemistry | Hou Z.,RIKEN | Li X.,RIKEN
Chemical Communications | Year: 2010

Aminophenyl functionalized cyclopentadienyl ligated rare-earth metal allyl mediated cationic systems display high cis-1,4 selectivity for the polymerization of isoprene, and living reversible and rapid chain transfer to aluminium additives. © The Royal Society of Chemistry 2010.


Yang C.,CAS Changchun Institute of Applied Chemistry | Yang C.,University of Chinese Academy of Sciences | Wang Y.,CAS Changchun Institute of Applied Chemistry | Wang Y.,University of Chinese Academy of Sciences | And 2 more authors.
Biosensors and Bioelectronics | Year: 2011

This work presents an aptasensor for Ochratoxin A (OTA) using unmodified gold nanoparticles (AuNPs) indicator. The assay method is based on the conformation change of OTA's aptamer in phosphate buffered saline (PBS) containing Mg2+ and OTA, and the phenomenon of salt-induced AuNPs aggregation. A single measurement took only five minutes. Circular dichroism spectroscopic experiments revealed for the first time that upon the addition of OTA, the conformation of OTA's aptamer in PBS buffer changed from random coil structure to compact rigid antiparallel G-quadruplex structure. This compact rigid G-quadruplex structure could not protect AuNPs against salt-induced aggregation, and thus the color change from red to blue could be observed by the naked eye. The linear range of the colorimetric aptasensor covered a large variation of OTA concentration from 20 to 625nM and the detection limit of 20nM (3σ) was obtained. © 2010 Elsevier B.V.


Yang C.,CAS Changchun Institute of Applied Chemistry | Yang C.,University of Chinese Academy of Sciences | Lates V.,University of Perpignan | Prieto-Simon B.,Institute Of Bioenginyeria Of Catalonia Ibec | And 2 more authors.
Biosensors and Bioelectronics | Year: 2012

We report an aptasensor for biosensing of Ochratoxin A (OTA) using aptamer-DNAzyme hairpin as biorecognition element. The structure of this engineered nucleic acid includes the horseradish peroxidase (HRP)-mimicking DNAzyme and the OTA specific aptamer sequences. A blocking tail captures a part of these sequences in the stem region of the hairpin. In the presence of OTA, the hairpin is opened due to the formation of the aptamer-analyte complex. As a result, self-assembly of the active HRP-mimicking DNAzyme occurs. The activity of this DNAzyme is linearly correlated with OTA concentration up to 10. nM, showing a limit of detection of 2.5. nM. © 2011 Elsevier B.V.


Dang S.,CAS Changchun Institute of Applied Chemistry | Zhang J.-H.,CAS Fujian Institute of Research on the Structure of Matter | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry | Sun Z.-M.,CAS Fujian Institute of Research on the Structure of Matter
Journal of Materials Chemistry | Year: 2012

A new family of lanthanide metal-organic frameworks, LnL (Ln = Y, La-Yb, except Pm), were synthesized under hydrothermal conditions based on a semi-rigid trivalent carboxylic acid. All LnMOFs are isostructural based upon the analyses of single crystal and powder X-ray diffractions. The optical properties of compounds LnL can be easily tuned by doping methods, allowing for the syntheses of the materials with enhanced visible emission properties. Considering the intense blue-emission of the Dy compounds, it is expected that white light can be achieved by doping Dy and other red-emission lanthanide ions, such as Eu 3+ or Sm 3+. For the first time, without involving any emission from organic ligands, white-light emission was successfully realized by codoping Dy/Eu or Dy/Sm into analogic Gd compounds. © 2012 The Royal Society of Chemistry.


Dang S.,CAS Changchun Institute of Applied Chemistry | Ma E.,CAS Fujian Institute of Research on the Structure of Matter | Sun Z.-M.,CAS Changchun Institute of Applied Chemistry | Sun Z.-M.,CAS Fujian Institute of Research on the Structure of Matter | Zhang H.,CAS Changchun Institute of Applied Chemistry
Journal of Materials Chemistry | Year: 2012

A new series of lanthanide metal-organic frameworks, LnL (Ln = La, Y, Eu, Tb, and Gd), were prepared under hydrothermal conditions. The five compounds are all isostructural as confirmed by the analyses of single crystal and powder X-ray diffractions. The compounds exhibit layer-like structures with the [H 2NMe 2] + cations being located in the interlayer channels, which can be easily replaced by a number of metal ions. Most interestingly, compound EuL performs as a rare example of a highly selective and sensitive luminescence sensor for Fe 3+ ions based on total quenching of the Eu-luminescence via cation-exchange. The possible sensing mechanism was further explored in detail. Remarkably, it is the first Eu-MOF luminescent material to exhibit an excellent ability for the detection of Fe 3+ ions in a biological system. © The Royal Society of Chemistry 2012.


Jian Z.,CAS Changchun Institute of Applied Chemistry | Jian Z.,University of Chinese Academy of Sciences | Cui D.,CAS Changchun Institute of Applied Chemistry | Hou Z.,RIKEN
Chemistry - A European Journal | Year: 2012

A series of rare-earth-metal-hydrocarbyl complexes bearing N-type functionalized cyclopentadienyl (Cp) and fluorenyl (Flu) ligands were facilely synthesized. Treatment of [Y(CH 2SiMe 3) 3(thf) 2] with equimolar amount of the electron-donating aminophenyl-Cp ligand C 5Me 4H-C 6H 4-o-NMe 2 afforded the corresponding binuclear monoalkyl complex [({C 5Me 4-C 6H 4-o-NMe(μ-CH 2)}Y{CH 2SiMe 3}) 2] (1a) via alkyl abstraction and C-H activation of the NMe 2 group. The lutetium bis(allyl) complex [(C 5Me 4-C 6H 4-o-NMe 2)Lu(η 3-C 3H 5) 2] (2b), which contained an electron-donating aminophenyl-Cp ligand, was isolated from the sequential metathesis reactions of LuCl 3 with (C 5Me 4-C 6H 4-o-NMe 2)Li (1 equiv) and C 3H 5MgCl (2 equiv). Following a similar procedure, the yttrium- and scandium-bis(allyl) complexes, [(C 5Me 4-C 5H 4N) Ln(η 3-C 3H 5) 2] (Ln=Y (3a), Sc (3b)), which also contained electron-withdrawing pyridyl-Cp ligands, were also obtained selectively. Deprotonation of the bulky pyridyl-Flu ligand (C 13H 9-C 5H 4N) by [Ln(CH 2SiMe 3) 3(thf) 2] generated the rare-earth-metal-dialkyl complexes, [(η 3-C 13H 8-C 5H 4N)Ln(CH 2SiMe 3) 2(thf)] (Ln=Y (4a), Sc (4b), Lu (4c)), in which an unusual asymmetric η 3-allyl bonding mode of Flu moiety was observed. Switching to the bidentate yttrium-trisalkyl complex [Y(CH 2C 6H 4-o-NMe 2) 3], the same reaction conditions afforded the corresponding yttrium bis(aminobenzyl) complex [(η 3-C 13H 8-C 5H 4N)Y(CH 2C 6H 4-o-NMe 2) 2] (5). Complexes 1-5 were fully characterized by 1H and 13C NMR and X-ray spectroscopy, and by elemental analysis. In the presence of both [Ph 3C][B(C 6F 5) 4] and AliBu 3, the electron-donating aminophenyl-Cp-based complexes 1 and 2 did not show any activity towards styrene polymerization. In striking contrast, upon activation with [Ph 3C][B(C 6F 5) 4] only, the electron-withdrawing pyridyl-Cp-based complexes 3, in particular scandium complex 3b, exhibited outstanding activitiy to give perfectly syndiotactic (rrrr >99%) polystyrene, whereas their bulky pyridyl-Flu analogues (4 and 5) in combination with [Ph 3C][B(C 6F 5) 4] and AliBu 3 displayed much-lower activity to afford syndiotactic-enriched polystyrene. A rare gem: Rare-earth-metal-a