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Wang W.,CAS Beijing National Laboratory for Molecular | Ma Y.,CAS Beijing National Laboratory for Molecular | Qi L.,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2017

The booming development of organometal halide perovskites has prompted the exploration of morphology-engineering strategies to improve their performance in optoelectronic applications. However, the preparation of optoelectronic devices of perovskites with complex architectures and desirable properties is still highly challenging. Herein, novel CH3NH3PbI3 nanonets and nanobowl arrays are fabricated facilely by using monolayer colloidal crystal (MCC) templates on different substrates. Specifically, highly ordered CH3NH3PbI3 nanonets with high crystallinity are fabricated on a variety of flat substrates, whereas regular CH3NH3PbI3 nanobowl arrays are produced on a coarse substrate. The photodetection performance of the CH3NH3PbI3 nanonet-based photodetectors is significantly enhanced compared to the photodetectors based on conventional CH3NH3PbI3 compact films. Particularly, the nanonet photodetectors exhibit a high responsivity (10.33 A W-1 under 700 nm monochromatic light), which is six times higher than that for the compact CH3NH3PbI3 film devices, fast response speed, and good stability. Owing to the two-dimensional arrayed structure, the CH3NH3PbI3 nanonets exhibit an enhanced light harvesting ability and offer direct carrier transport pathways. Meanwhile, the MCC template brings about larger grain sizes with enhanced crystallinity. Furthermore, the perovskite nanonets can be formed on a flexible polyethylene terephthalate substrate for the fabrication of promising flexible nanonet photodetectors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lou N.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular | Gan L.,CAS Beijing National Laboratory for Molecular
Angewandte Chemie - International Edition | Year: 2017

Selective addition to the C70 cage divides its π-conjugated system into various smaller π-conjugated systems with enhanced fluorescent properties. Key reactions include chlorination, methoxylation, ozonation, and Bingel or Bingel-Hirsch reactions. The maximum emission wavelength of the C70 multiadducts ranges from 450 to 655nm. Among the C70 multiadducts, C70(OMe)8(C(COOEt)2)3 showed the highest quantum yield (ΦF=0.18) and largest Stokes shift (402nm), with maximum emission at 655nm. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang L.,CAS Shanghai Institute of Organic Chemistry | Chen H.,CAS Beijing National Laboratory for Molecular | Deng L.,CAS Shanghai Institute of Organic Chemistry
Journal of the American Chemical Society | Year: 2017

Transition-metal alkylidenes are important reactive organometallic intermediates, and our current knowledge on them has been mainly restricted to those with closed-shell electronic configurations. In this study, we present an exploration on open-shell iron alkylidenes with a weak-field tripodal amido-phosphine-amido ligand. We found that a high-spin (amido-phosphine-amido)iron(II) complex can react with (p-tolyl)2CN2 to afford a high-spin (amido-ylide-amido)iron(II) complex, 2, which could transfer its alkylidene moiety to a variety of alkenes, either the electron-rich or electron-deficient ones, to form cyclopropane derivatives. The reaction of 2 with cis-β-deuterio-styrene gave deuterated cyclopropane derivatives with partial loss of the stereochemical integrity with respect to the cis-styrene. Kinetic study on the cyclopropanation reaction of 2 with 4-fluoro-styrene disclosed the activation parameters of ΔH⧧ = 23 ± 1 kcal/mol and ΔS⧧ = −20 ± 3 cal/mol/K, which are comparable to those of the cyclopropanation reactions involving transition-metal alkylidenes. However, the cyclopropanation of para-substituted styrenes by 2 shows a nonlinear Hammett plot of log(kX/kH) vs σp. By introduction of a radical parameter, a linear plot of log(kX/kH) vs 0.59σp + 0.55σc • was obtained, which suggests the “nucleophilic” radical nature of the transition state of the cyclopropanation step. In corroboration with the experimental observations, density functional theory calculation on the reaction of 2 with styrene suggests the involvement of an open-shell (amido-phosphine-amido)iron alkylidene intermediate that is higher in energy than its (amido-ylide-amido)iron(II) precursor and an “outer-sphere” radical-type mechanism for the cyclopropanation step. The negative charge distribution on the alkylidene carbon atoms of the open-shell states (S = 2 and 1) explains the high activity of the cyclopropanation reaction toward electron-deficient alkenes. The study demonstrates the unique activity of open-shell iron alkylidene species beyond its closed-shell analogues, thus pointing out their potential synthetic usage in catalysis. © 2017 American Chemical Society.


Li Z.,CAS Beijing National Laboratory for Molecular | Liu Z.,CAS Beijing National Laboratory for Molecular
Nano Research | Year: 2017

The introduction of lattice anisotropy causes Dirac cones to shift in response to the applied strain, leaving a pseudogap at the original Dirac points. Here, a group-theory analysis is combined with first-principles calculations to reveal the movement characteristics of Dirac points and band gaps in various graphynes under rotating uniaxial and shear strains. Graphene, where linear effects dominate, is different from α-, β-, and γ-graphynes, which generate strong nonlinear responses due to their bendable acetylenic linkages. However, the linear components of the electronic response, which are essential in determining material performance such as intrinsic carrier mobility due to electron–phonon coupling, can be readily separated, and are well described by a unified theory. The movement of the Dirac points in α-graphyne is circular under a rotating strain, and the pseudogap opening is isotropic with a magnitude of only 2% that in graphene. In comparison, the movement in β-graphyne is elliptical and the center is displaced from the origin. For γ-graphyne, three branches of gaps change with the applied strains with a sine/cosine dependence on the strain angle. The developed methodology is useful in determining the electronic response to various strains of Dirac materials and two-dimensional semiconductors. [Figure not available: see fulltext.] © 2016 Tsinghua University Press and Springer-Verlag Berlin Heidelberg


Wang L.-X.,CAS Beijing National Laboratory for Molecular | Tang Y.-L.,CAS Beijing National Laboratory for Molecular
European Journal of Organic Chemistry | Year: 2017

Nitrogen-containing heterocycles are found in a vast number of natural products and biologically active compounds, and have attracted a lot of attention. Among all the reported methods, cycloisomerization transformations involving the activation of alkynes with the aid of transition metals are a very active area in synthetic organic chemistry. This review covers the most important recent advances in the use of metal-catalyzed or metal-free cycloisomerizations for the preparation of indolizines and indolizinones from starting substrates consisting of pyridine-containing propargylic esters or alcohols. Cycloisomerization transformations to heterocycles are very efficient and atom-economic, and we hope that this review will result in further focused research to widen the application of indolizines and indolizinones. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan C.,CAS Beijing National Laboratory for Molecular | Yan C.,University of Chinese Academy of Sciences | Wang T.,CAS Beijing National Laboratory for Molecular | Wang T.,University of Chinese Academy of Sciences
Chemical Society Reviews | Year: 2017

Studies on nanoparticle assemblies and their applications have been research frontiers in nanoscience in the past few decades and remarkable progress has been made in the synthetic strategies and techniques. Recently, the design and fabrication of the nanoparticle-based nanomaterials or nanodevices with integrated and enhanced properties compared to those of the individual components have gradually become the mainstream. However, a systematic solution to provide a big picture for future development and guide the investigation of different aspects of the study of nanoparticle assemblies remains a challenge. The binary cooperative complementary principle could be an answer. The binary cooperative complementary principle is a universal discipline and can describe the fundamental properties of matter from the subatomic particles to the universe. According to its definition, a variety of nanoparticle assemblies, which represent the cutting-edge work in the nanoparticle studies, are naturally binary cooperative complementary materials. Therefore, the introduction of the binary cooperative complementary principle in the studies of nanoparticle assemblies could provide a unique perspective for reviewing this field and help in the design and fabrication of novel functional nanoparticle assemblies. © The Royal Society of Chemistry 2017.


Dong H.,CAS Beijing National Laboratory for Molecular | Bo Z.,Beijing Normal University | Hu W.,CAS Beijing National Laboratory for Molecular
Macromolecular Rapid Communications | Year: 2011

A planar conjugated copolymer named HXS-1 was applied in thin film phototransistors. Similar to organic field-effect transistors using V G to control the source-drain current, in phototransistors, the light is used to substitute V G as an independent variable to control the output of the transistors to realize light detection and signal magnification in a single organic device. All devices exhibited high performance with an on/off ratio up to 4.6×10 4 (the highest on/off ratio of organic or polymer phototransistors), which could be assigned to i) the wide absorption features of HXS-1 in the whole UV-vis range, ii) the ideal HOMO energy level of HXS-1 (5.21 eV) to align with Au electrodes (5.2 eV) and iii) the high mobility of the polymer thin films (∼0.06 cm 2/Vs). Moreover, the devices, both under continuous operation conditions and long term measurement conditions, exhibited excellent stability, indicating potential applications of the devices in polymer-based optoelectronics. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lin Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,University of Chinese Academy of Sciences | Zhan X.,Peking University
Materials Horizons | Year: 2014

Although fullerenes and their derivatives, such as PCBM, have been the dominant electron-acceptor materials in organic photovoltaic cells (OPVs), they suffer from some disadvantages, such as weak absorption in the visible spectral region, limited spectral breadth and difficulty in variably tuning the band gap. It is necessary to explore non-fullerene electron acceptors that will not only retain the favorable electron-accepting and transporting properties of fullerenes but also overcome their insufficiencies. After a decade of mediocrity, non-fullerene acceptors are undergoing rapid development and are emerging as a hot area of focus in the field of organic semiconductors. Solution-processed bulk heterojunction (BHJ) OPVs based on non-fullerene acceptors have shown encouraging power conversion efficiencies of over 4%. This article reviews recent developments in several classes of solution-processable non-fullerene acceptors for BHJ OPVs. The remaining problems and challenges along with the key research directions in the near future are discussed. © The Royal Society of Chemistry 2014.


Liu S.,Peking University | Zhang X.,CAS Beijing National Laboratory for Molecular | Luo W.,CAS Beijing National Laboratory for Molecular | Wang Z.,Peking University | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2011

Filling in the gap: Label-free, real-time electrical detection of proteins is achieved with high selectivity and real single-molecule sensitivity by using aptamer-functionalized molecular electronic devices with single-walled carbon nanotubes as point contacts. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Shen J.,CAS Beijing National Laboratory for Molecular | Sun L.-D.,CAS Beijing National Laboratory for Molecular | Zhu J.-D.,Peking University | Wei L.-H.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Advanced Functional Materials | Year: 2010

Lanthanide nanoparticles (NPs), characterized by their large Stokes shifts, narrow emission bands and high photochemical stability, are promising candidates for optical probes in biological research. As a typical red emission material, Eu3+-doped YVO4 is investigated in pursuit of an integral methodology for Ln-based bioprobes. Assisted with phosphino- polyacrylic acid, YVO4:Eu NPs with a luminescent quantum yield of ca. 54% are synthesized via a one-pot hydrothermal reaction. The obtained NPs exhibit good water/buffer stability and feasible biomodification benefiting from the surface carboxylic acid groups. However, having an inorganic core of ca. 20 nm, these NPs do not affect the conformation of surface conjugated proteins (bovine serum albumin), as confirmed with the circular dichroism spectrum. A specific recognition protocol is demonstrated by biotinated YVO4:Eu NPs in quantitative fluoroimmunoassay and microchip assay. Furthermore, the biocompatibility of the Ln NPs, which is an important aspect towards biological application, is demonstrated with the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide] assay. Cell imaging studies conducted with spectral mapping technique and confocal fluorescent microscopy demonstrate the YVO 4:Eu NPs to be a type of competitive luminescent probes for in vitro applications. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lin Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,University of Chinese Academy of Sciences | Wang Y.,CAS Beijing National Laboratory for Molecular | Wang Y.,University of Chinese Academy of Sciences | And 5 more authors.
Advanced Materials | Year: 2014

A novel nonplanar star-shaped perylene diimide acceptor with a triphenylamine core (S(TPA-PDI)) is explored and applied in solution-processed organic solar cells. These solar cells exhibit an encouraging power conversion efficiency of up to 3.32%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang W.,Peking University | Zhao Q.,Peking University | Li H.,Peking University | Wu H.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Advanced Functional Materials | Year: 2012

Transparent, double-sided, flexible, ITO-free dye-sensitized solar cells (DSSCs) are fabricated in a simple, facile, and controllable way. Highly ordered, high-crystal-quality, high-density ZnO nanowire arrays are radially grown on stainless steel, Au, Ag, and Cu microwires, which serve as working electrodes. Pt wires serve as the counter electrodes. Two metal wires are encased in electrolyte between two poly(ethylene terephthalate) (PET) films (or polydimethylsiloxane (PDMS) films) to render the device both flexible and highly transparent. The effect of the dye thickness on the photovoltaic performance of the DSSCs as a function of dye-loading time is investigated systematically. Shorter dye-loading times lead to thinner dye layers and better device performance. A dye-loading time of 20 min results in the best device performance. An oxidation treatment of the metal wires is developed effectively to avoid the galvanic-battery effect found in the experiment, which is crucial for real applications of double-metal-wire DSSC configurations. The device shows very good transparency and can increase sunlight use efficiency through two-sided illumination. The double-wire DSSCs remain stable for a long period of time and can be bent at large angles, up to 107°, reversibly, without any loss of performance. The double-wire-PET, planar solar-cell configuration can be used as window stickers and can be readily realized for large-area-weave roll-to-roll processing. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Xiang D.,CAS Beijing National Laboratory for Molecular | Xiang D.,Nankai University | Wang X.,CAS Beijing National Laboratory for Molecular | Jia C.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Chemical Reviews | Year: 2016

Creating functional electrical circuits using individual or ensemble molecules, often termed as "molecular-scale electronics", not only meets the increasing technical demands of the miniaturization of traditional Si-based electronic devices, but also provides an ideal window of exploring the intrinsic properties of materials at the molecular level. This Review covers the major advances with the most general applicability and emphasizes new insights into the development of efficient platform methodologies for building reliable molecular electronic devices with desired functionalities through the combination of programmed bottom-up self-assembly and sophisticated top-down device fabrication. First, we summarize a number of different approaches of forming molecular-scale junctions and discuss various experimental techniques for examining these nanoscale circuits in details. We then give a full introduction of characterization techniques and theoretical simulations for molecular electronics. Third, we highlight the major contributions and new concepts of integrating molecular functionalities into electrical circuits. Finally, we provide a critical discussion of limitations and main challenges that still exist for the development of molecular electronics. These analyses should be valuable for deeply understanding charge transport through molecular junctions, the device fabrication process, and the roadmap for future practical molecular electronics. © 2016 American Chemical Society.


Cheng P.,CAS Beijing National Laboratory for Molecular | Cheng P.,University of Chinese Academy of Sciences | Zhan X.,Peking University
Chemical Society Reviews | Year: 2016

Organic solar cells (OSCs) present some advantages, such as simple preparation, light weight, low cost and large-area flexible fabrication, and have attracted much attention in recent years. Although the power conversion efficiencies have exceeded 10%, the inferior device stability still remains a great challenge. In this review, we summarize the factors limiting the stability of OSCs, such as metastable morphology, diffusion of electrodes and buffer layers, oxygen and water, irradiation, heating and mechanical stress, and survey recent progress in strategies to increase the stability of OSCs, such as material design, device engineering of active layers, employing inverted geometry, optimizing buffer layers, using stable electrodes and encapsulation. Some research areas of device stability that may deserve further attention are also discussed to help readers understand the challenges and opportunities in achieving high efficiency and high stability of OSCs towards future industrial manufacture. © 2016 The Royal Society of Chemistry.


Lin Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,University of Chinese Academy of Sciences | Ma L.,University of Chinese Academy of Sciences | Li Y.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Advanced Energy Materials | Year: 2013

Organic photovoltaic devices and solar cells (OPVs) that can be fabricated by simple solution processing techniques are under intense investigation in academic and industrial laboratories because of their potential to enable mass production of lightweight, fl exible and cost-effective devices. [ 1-4 ] Much of the focus has been on the development of polymer-based OPVs which have seen a dramatic rise in effi ciency over the last decade, and the encouraging power conversion effi ciency (PCE) over 9% has been achieved from bulk heterojunction (BHJ) OPVs based on polymer donors and fullerene acceptors. [ 5 ] Compared with their polymer counterparts, small molecules offer potential advantages in terms of defi ned molecular structure, defi nite molecular weight, easy purifi cation, easy mass-scale production, and good batch-to-batch reproducibility. [ 6-10 ] Recently, great efforts have been dedicated to develop small molecules for application in solar cells, such as linear molecules, [ 11-23 ] star-shaped molecules, [ 24-28 ] and other organic dyes; [ 29 , 30 ] and, so far, the highest PCEs of solution-processed OPVs based on small molecular donors and [6,6]-phenyl-C 61 (or C 71 )-butyric-acid-methyl-ester (PC 61 BM or PC 71 BM) acceptors are over 6% [ 15 , 17 ] and 7%, [ 19 , 20 ] respectively. Despite the fact that considerable progress has been made in small molecule-based OPVs, the relatively low PCE is hindrance to commercialization of these devices.© 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.


Lin Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,University of Chinese Academy of Sciences | Li Y.,CAS Beijing National Laboratory for Molecular | Zhan X.,CAS Beijing National Laboratory for Molecular | Zhan X.,Peking University
Advanced Energy Materials | Year: 2013

A novel linear non-fullerene acceptor (DBS-2DPP) based on dibenzosilole and diketopyrrolopyrrole is designed and synthesized. DBS-2DPP exhibits strong and broad absorption and appropriate energy levels matching with P3HT. Solution-processed BHJ OSCs based on P3HT:DBS-2DPP show PCEs as high as 2.05%. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ouyang K.,CAS Beijing National Laboratory for Molecular | Ouyang K.,Peking University | Liang Y.,Hunan Normal University | Xi Z.,Peking University
Organic Letters | Year: 2012

A variety of silacycles including benzosiloles, six- and eight-membered silacyclic skeletons, were efficiently synthesized via a Pd-catalyzed intramolecular Mizoroki-Heck reaction of vinylsilanes. © 2012 American Chemical Society.


Pan F.,CAS Beijing National Laboratory for Molecular | Wang H.,Peking University | Shen P.-X.,CAS Beijing National Laboratory for Molecular | Zhao J.,Peking University | And 2 more authors.
Chemical Science | Year: 2013

A novel rhodium-catalyzed C-C bond formation was developed to construct biaryls through unreactive aryl C-S bond cleavage of thioethers with aryl boroxines. This protocol provided a supplemental method of traditional Suzuki-Miyaura coupling. This journal is © The Royal Society of Chemistry 2013.


Wen L.,CAS Beijing National Laboratory for Molecular | Liu Q.,Beijing Normal University | Ma J.,CAS Beijing National Laboratory for Molecular | Tian Y.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Advanced Materials | Year: 2012

A highly efficient and perfectly reversible ionic gate that can be activated by pH or UV light is demonstrated. Switching between the OFF state and the ON state is mainly dependent on the surface charge transition brought about by a malachite green derivative attached to the interior surface of an ion track-etched conical nanochannel, which makes it suitable for confined spaces. Applications in electronics, actuators, and biosensors can be foreseen. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lin Y.,CAS Beijing National Laboratory for Molecular | Ma L.,University of Chinese Academy of Sciences | Li Y.,Peking University | Liu Y.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Advanced Energy Materials | Year: 2014

An oligothiophene-based molecule (BDT-3T-CA) using a molecular engineering approach is applied to solution-processed layer-by-layer solar cells. The solar cells based on BDT-3T-CA/PC61BM (a fullerene derivative) exhibit power conversion efficiency (PCE) values as high as 4.16% and fill factor (FF) values up to 0.75. The FF of 0.75 is the highest value reported for solution processed small molecule solar cells. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cheng P.,CAS Beijing National Laboratory for Molecular | Cheng P.,University of Chinese Academy of Sciences | Hou J.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular | Zhan X.,Peking University
Advanced Energy Materials | Year: 2014

Polymer solar cells (PSCs) are fabricated without solvent additives using a low-bandgap polymer, PBDTTT-C-T, as the donor and [6,6]-phenyl-C61-butyric- acid-methyl-ester (PC61BM) as the acceptor. Donor-acceptor blend and layer-by-layer (LL) solution process are used to form active layers. Relative to the blend devices, the LL devices exhibit stronger absorption, better vertical phase separation, higher hole and electron mobilities, and better charge extraction at correct electrodes. As a result, after thermal annealing the LL devices exhibit an average power conversion efficiency (PCE) of 6.86%, which is much higher than that of the blend devices (4.31%). The best PCE of the LL devices is 7.13%, which is the highest reported for LL processed PSCs and among the highest reported for PC61BM-based single-junction PSCs. Polymer solar cells are fabricated without solvent additives using a low-bandgap polymer, PBDTTT-C-T, as the donor and [6,6]-phenyl-C61-butyric-acid-methyl-ester (PC61BM) as the acceptor. After thermal annealing, layer-by-layer solution processed devices exhibit a power conversion efficiency as high as 7.13%, which is much higher than that of blend devices (4.49%), due to efficient vertical phase separation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


He Y.-M.,CAS Beijing National Laboratory for Molecular | Feng Y.,CAS Beijing National Laboratory for Molecular | Fan Q.-H.,CAS Beijing National Laboratory for Molecular
Accounts of Chemical Research | Year: 2014

Conspectus The transition metal complexes containing chiral phosphorus ligands are the most widely and successfully used catalysts in asymmetric hydrogenation of unsaturated compounds. However, a major problem associated with these homogeneous catalytic systems is the separation and recycling of the often expensive and easily oxidized chiral catalysts. In addition, many hydrogenation reactions still lack efficient chiral catalysts, and the stereoselectivities in many hydrogenation reactions are substrate-dependent. Therefore, the development of highly effective and recyclable chiral phosphorus catalysts is highly desirable.Over the past few decades, a number of chiral catalysts have been successfully anchored onto different supports, such as cross-linked polymeric resins and inorganic materials. However, most of the classical supported chiral catalysts suffered from inferior catalytic properties to their homogeneous counterparts due to poor accessibility, random anchoring, and disturbed geometry of the active sites in the solid matrix. To overcome this drawback, dendrimers, which have well-defined and globular macromolecular architectures serve as a promising type of soluble catalyst support. The catalytic sites are generally located at the core or on the periphery of the dendrimer, and the resulting dendritic catalysts are designable. Incorporation of a chiral catalyst into a sterically demanding dendrimer will create a specific microenvironment around the catalytic site and thus influence the catalytic performance of the metal center, like an enzyme does.In this Account, we survey the development of core-functionalized chiral dendritic phosphorus ligands for asymmetric hydrogenation mainly by our research group. Several series of chiral dendritic phosphorus ligands, including diphosphines, monodentate phosphoramidites, and P,N-ligands, have been synthesized by attaching the corresponding chiral phosphorus units into the core or the focal point of Fréchet-type dendrons. Their transition metal (Ru, Rh, or Ir) complexes have been applied in the asymmetric hydrogenation of prochiral olefins and ketones, as well as some challenging imine-type substrates. All reactions were carried out in a homogeneous manner, and the structure-property relationships in some cases were established. The sterically demanding dendritic wedges were found to play important roles in catalytic properties, and better catalytic activities or enantioselectivities or both than those obtained from the corresponding monomeric catalysts were achieved in most cases. In addition, the dendritic catalysts could be readily recycled by means of solvent precipitation, water- or temperature-induced two-phase separation. Our study has thus demonstrated that dendrimer catalysis could combine the advantages of both classical heterogeneous and homogeneous catalysis. © 2014 American Chemical Society.


Zou Z.,CAS Beijing National Laboratory for Molecular | Fu L.,CAS Beijing National Laboratory for Molecular | Song X.,CAS Beijing National Laboratory for Molecular | Zhang Y.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Nano Letters | Year: 2014

Early transition metals, especially groups IVB-VIB metals, can form stable carbides, which are known to exhibit excellent "noble-metal-like" catalytic activities. We demonstrate herein the applications of groups IVB-VIB metals in graphene growth using atmospheric pressure chemical vapor deposition technique. Similar to the extensively studied Cu, Ni, and noble metals, these transition-metal foils facilitate the catalytic growth of single- to few-layer graphene. The most attractive advantage over the existing catalysts is their perfect control of layer thickness and uniformity with highly flexible experimental conditions by in situ converting the dissolved carbons into stable carbides to fully suppress the upward segregation/precipitation effect. The growth performance of graphene on these transition metals can be well explained by the periodic physicochemical properties of elements. Our work has disclosed a new territory of catalysts in the periodic table for graphene growth and is expected to trigger more interest in graphene research. © 2014 American Chemical Society.


Zhuo J.,Peking University | Wang T.,Peking University | Zhang G.,CAS Beijing National Laboratory for Molecular | Liu L.,Peking University | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2013

Full(erene) of surprises: The first isomerically pure multi-hydroxylated fullerene, C60(OH)8, shows a reduction peak and a reoxidation peak in aqueous solution. With surprising catalytic performance in the hydrogen evolution reaction (HER), when electrodeposited on a glassy carbon electrode (GCE), salts of C60(OH)8 may prove to be effective molecular catalysts for conducting the HER without transition metals. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu J.,Peking University | Zhou J.,CAS Beijing National Laboratory for Molecular | Luo Y.,Peking University
Bioconjugate Chemistry | Year: 2012

A neutral cross-linked dendritic system is described for use of delivering small interfering RNA (siRNA) for targeted gene silencing. By replacing the terminal amines with hydrazide groups and N-acetylgalactosamine (GalNAc) ligands, cationic polyamidoamine (PAMAM) dendrimers were transformed into neutral glycosylated carriers for siRNA delivery. Mainly owing to the pH sensitivity and the proton-absorption capability of the tertiary amines within the interior branches, these PAMAM derivatives showing neutrality under physiological conditions (pH 7.4) formed complexes with siRNA through electrostatic interactions at pH 5. Cross-linking procedures via reactions with glutaraldehyde were established, and cytocompatible cross-linked systems loaded with siRNA obtained, with the particulate properties variable with the cross-linking condition and the GalNAc level in the dendritic carrier. In vitro cellular uptake and RNAi experiments showed that the cross-linked dendritic systems with an appropriate level of GalNAc composition effectively interacted with HepG2 cells and inhibited the expression of a luciferase reporter gene. Neutral cross-linked dendritic systems provide a new paradigm for designing siRNA delivery systems with biocompatibility and targeting capability. © 2012 American Chemical Society.


Wang Y.,CAS Beijing National Laboratory for Molecular | Zhan X.,Peking University
Advanced Energy Materials | Year: 2016

Layer-by-layer (LL) processes, i.e., sequential deposition of different active layers, are widely used in the fabrication of organic solar cells (OSCs). Recently, LL vacuum deposition and LL solution processes have attracted considerable attention. LL processing presents some advantages over the blend method: a) donor and acceptor layers can be easily and independently controlled and optimized; b) the charge carriers dissociated from excitons at the donor-acceptor interface are confined to each phase, so bimolecular recombination losses can be reduced; c) bilayer geometries enable an easier way for understanding the physical processes taking place at the donor-acceptor interface; d) desired vertical phase separation for charge extraction can be obtained through changing the sequence of donor and acceptor deposition. This report summarizes the recent developments of LL processed OSCs. The remaining problems and challenges, and the key research direction in near future are discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Xie R.,CAS Beijing National Laboratory for Molecular | Hong S.,Peking University | Feng L.,CAS Beijing National Laboratory for Molecular | Rong J.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Journal of the American Chemical Society | Year: 2012

A cell-specific metabolic glycan labeling strategy has been developed using azidosugars encapsulated in ligand-targeted liposomes. The ligands are designed to bind specific cell-surface receptors that are only expressed or up-regulated in target cells, which mediates the intracellular delivery of azidosugars. The delivered azidosugars are metabolically incorporated into cell-surface glycans, which are then imaged via a bioorthogonal reaction. © 2012 American Chemical Society.


Pei J.,Peking University | Yin N.,Peking University | Ma X.,Peking University | Lai L.,Peking University | And 2 more authors.
Journal of the American Chemical Society | Year: 2014

In this Perspective, we focus on new, systems-centric views of structure-based drug design (SBDD) that we believe will impact future drug discovery research and development. We will first discuss new ways to identify drug targets based on systems intervention analysis, and then we will introduce emerging SBDD methods driven by advancements in systems biology. © 2014 American Chemical Society.


Wu J.,CAS Beijing National Laboratory for Molecular | Hou Y.,Peking University | Gao S.,CAS Beijing National Laboratory for Molecular
Nano Research | Year: 2011

In this work, FePt-Au heterostructured nanocrystals (HNCs) such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods (NRs). A study of the growth mechanism revealed that the morphology control of the final products can be correlated with the adsorption sites of hydrogen onto the FePt NRs, which can be manipulated by the amount of the forming gas (Ar/7% H2) added. Not only the optical characteristic and magnetic properties of the intrinsic materials were retained in the products, but also the FePt-Au HNCs showed the tunable multifunctional properties resulted from the interactions between Au and FePt. Moreover, for methanol oxidation, the FePt-Au HNCs exhibited enhanced catalytic activity and CO tolerance on the catalyst surface compared to commercial Pt catalysts. It is worth noting that as multifunctional units, the FePt-Au HNCs also possess a heterogeneous surface, which could potentially enable their site-specific functionalization for targeting or imaging purposes in biomedical applications. More interestingly, the catalytic properties of the FePt-Au HNCs also endow this material with application potentials in nanocatalysis. © 2011 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.


Suo T.,CAS Beijing National Laboratory for Molecular | Yan D.,Beijing Normal University
Polymer | Year: 2011

A theoretical study on the phase behaviors of a polymer solution confined between two coaxial cylindrical walls is presented. For the case of a neutral inner cylinder, the spinodal point derived by the Gaussian fluctuation theory is confinement-independent because of the existence of a free dimension in the system. The kinetic analysis indicates that the fluctuation modes always have a component of a plane wave along the axial direction, which can lead to the formation of a periodic-like concentration pattern. On the other hand, the equilibrium structure of the system is obtained by the self-consistent mean-field theory (SCMFT) and the interplay between the "wetting" phenomenon and the phase separation is observed by modifying the property of the inner cylindrical wall. In particular, our results can be regarded as a hint to interpret the mechanism of the formation of the shish-kebab structure observed in the field of polymer crystallization. © 2011 Elsevier Ltd.


Wang H.,Shanghai University | Yang S.-T.,Shanghai University | Yang S.-T.,Southwest University for Nationalities | Cao A.,Shanghai University | And 2 more authors.
Accounts of Chemical Research | Year: 2013

A diverse array of carbon nanomaterials (NMs), including fullerene, carbon nanotubes (CNTs), graphene, nanodiamonds, and carbon nanoparticles, have been discovered and widely applied in a variety of industries. Carbon NMs have been detected in the environment and have a strong possibility of entering the human body. The safety of carbon NMs has thus become a serious concern in academia and society. To achieve strict biosafety assessments, researchers need to fully understand the effects and fates of NMs in the human body, including information about absorption, distribution, metabolism, excretion, and toxicity (ADME/T).To acquire the ADME data, researchers must quantify NMs, but carbon NMs are very difficult to quantify in vivo. The carbon background in a typical biological system is high, particularly compared with the much lower concentration of carbon NMs. Moreover, carbon NMs lack a specific detection signal. Therefore, isotopic labeling, with its high sensitivity and specificity, is the first choice to quantify carbon NMs in vivo. Previously, researchers have used many isotopes, including 13C, 14C, 125I, 131I, 3H, 64Cu, 111In, 86Y, 99mTc, and 67Ga, to label carbon NMs. We used these isotopic labeling methods to study the ADME of carbon NMs via different exposure pathways in animal models.Except for the metabolism of carbon NMs, which has seldom been investigated, significant amounts of data have been reported on the in vivo absorption, distribution, excretion, and toxicity of carbon NMs, which have revealed characteristic behaviors of carbon NMs, such as reticuloendothelial system (RES) capture. However, the complexity of the biological systems and diverse preparation and functionalization of the same carbon NMs have led to inconsistent results across different studies. Therefore, the data obtained so far have not provided a compatible and systematic profile of biosafety. Further efforts are needed to address these problems.In this Account, we review the in vivo quantification methods of carbon NMs, focusing on isotopic labeling and tracing methods, and summarize the related labeling, purification, bio-sampling, and detection of carbon NMs. We also address the advantages, applicable situations, and limits of various labeling and tracing methods and propose guidelines for choosing suitable labeling methods. A collective analysis of the ADME information on various carbon NMs in vivo would provide general principles for understanding the fate of carbon NMs and the effects of chemical functionalization and aggregation of carbon NMs on their ADME/T in vivo and their implications in nanotoxicology and biosafety evaluations. © 2012 American Chemical Society.


Jia C.,CAS Beijing National Laboratory for Molecular | Guo X.,CAS Beijing National Laboratory for Molecular | Guo X.,Peking University
Chemical Society Reviews | Year: 2013

Understanding charge transport of single molecules or a small collection of molecules sandwiched between electrodes is of fundamental importance for molecular electronics. This requires the fabrication of reliable devices, which depend on several factors including the testbed architectures used, the molecule number and defect density being tested, and the nature of the molecule-electrode interface. On the basis of significant progresses achieved in both experiments and theory over the past decade, in this tutorial review, we focus on new insights into the influence of the nature of the molecule-electrode interface, the most critical issue hindering the development of reliable devices, on the conducting properties of molecules. We summarize the strategies developed for controlling the interfacial properties and how the coupling strength between the molecules and the electrodes modulates the device properties. These analyses should be valuable for deeply understanding the relationship between the contact interface and the charge transport mechanism, which is of crucial importance for the development of molecular electronics, organic electronics, nanoelectronics, and other interface-related optoelectronic devices. © 2013 The Royal Society of Chemistry.


Cheng Y.-J.,National Chiao Tung University | Hsieh C.-H.,National Chiao Tung University | He Y.,CAS Beijing National Laboratory for Molecular | Hsu C.-S.,National Chiao Tung University | Li Y.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2010

A poly(3-hexylthiophene) (P3HT)-based inverted solar cell using indene-C60 bis-adduct (ICBA) as the acceptor achieved a high open-circuit voltage of 0.82 V due to ICBA's higher-lying lowest unoccupied molecular orbital level, leading to an exceptional power-conversion efficiency (PCE) of 4.8%. By incorporating a cross-linked fullerene interlayer, C-PCBSD, to further modulate the interface characteristics, the ICBA:P3HT-based inverted device exhibited an improved short-circuit current and fill factor, yielding a record high PCE of 6.2%. © 2010 American Chemical Society.


Zhang C.,CAS Beijing National Laboratory for Molecular | Lai L.,Peking University
Biochemical Society Transactions | Year: 2011

Structure-based drug design for chemical molecules has been widely used in drug discovery in the last 30 years. Many successful applications have been reported, especially in the field of virtual screening based on molecular docking. Recently, there has been much progress in fragment-based as well as de novo drug discovery. As many protein-protein interactions can be used as key targets for drug design, one of the solutions is to design protein drugs based directly on the protein complexes or the target structure. Compared with protein-ligand interactions, protein-protein interactions are more complicated and present more challenges for design. Over the last decade, both sampling efficiency and scoring accuracy of protein-protein docking have increased significantly. We have developed several strategies for structurebased protein drug design. A grafting strategy for key interaction residues has been developed and successfully applied in designing erythropoietin receptor-binding proteins. Similarly to small-molecule design, we also tested de novo protein-binder design and a virtual screen of protein binders using protein-protein docking calculations. In comparison with the development of structure-based small-molecule drug design, we believe that structure-based protein drug design has come of age. ©The Authors Journal compilation ©2011 Biochemical Society.


Liu Z.,Peking University | Liu Z.,CAS Beijing National Laboratory for Molecular | Huang Y.,Peking University | Huang Y.,St Jude Childrens Research Hospital
Protein Science | Year: 2014

The past decade has witnessed great advances in our understanding of protein structure-function relationships in terms of the ubiquitous existence of intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs). The structural disorder of IDPs/IDRs enables them to play essential functions that are complementary to those of ordered proteins. In addition, IDPs/IDRs are persistent in evolution. Therefore, they are expected to possess some advantages over ordered proteins. In this review, we summarize and survey nine possible advantages of IDPs/IDRs: economizing genome/protein resources, overcoming steric restrictions in binding, achieving high specificity with low affinity, increasing binding rate, facilitating posttranslational modifications, enabling flexible linkers, preventing aggregation, providing resistance to non-native conditions, and allowing compatibility with more available sequences. Some potential advantages of IDPs/IDRs are not well understood and require both experimental and theoretical approaches to decipher. The connection with protein design is also briefly discussed. © 2014 The Protein Society.


Huang Y.,CAS Beijing National Laboratory for Molecular | Hu F.,CAS Beijing National Laboratory for Molecular | Zhao R.,CAS Beijing National Laboratory for Molecular | Zhang G.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Chemistry - A European Journal | Year: 2014

Smart molecular probes and flexible methods are attracting remarkable interest for the visualization of cancer-related biological and chemical events. In this work, a new fluorescence turn-on probe with dual-recognition characteristics for the specific imaging of cancer cells is reported. This new bioprobe is rationally designed by linking tetraphenylethylene (TPE), an aggregation-induced em Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang H.,CAS Beijing National Laboratory for Molecular | Hou X.,CAS National Center for Nanoscience and Technology | Zeng L.,Beijing Normal University | Yang F.,Beijing Normal University | And 4 more authors.
Journal of the American Chemical Society | Year: 2013

Bioinspired artificial functional nanochannels for intelligent molecular and ionic transport control at the nanoscale have wide potential applications in nanofluidics, energy conversion, and biosensors. Although various smart passive ion transport properties of ion channels have been artificially realized, it is still hugely challenging to achieve high level intelligent ion transport features in biological ion pumps. Here we show a unique bioinspired single ion pump based on a cooperative pH response double-gate nanochannel, whose gates could be opened and closed alternately/simultaneously under symmetric/asymmetric pH environments. With the stimulation of the double-gate nanochannel by continuous switching of the symmetric/asymmetric pH stimuli, the bioinspired system systematically realized three key ionic transport features of biological ion pumps, including an alternating gates ion pumping process under symmetric pH stimuli, transformation of the ion pump into an ion channel under asymmetric pH stimuli, and a fail-safe ion pumping feature under both symmetric and asymmetric pH stimuli. The ion pumping processes could well be reproduced under a concentration gradient. With the advantages of the extraordinary ionic transport functions of biological ion pumps, the bioinspired ion pump should find widespread applicability in active transportation-controlling smart nanofluidic devices, efficient energy conversions, and seawater desalinization, and open the way to design and develop novel bioinspired intelligent artificial nanochannel materials. © 2013 American Chemical Society.


Cheng P.,CAS Beijing National Laboratory for Molecular | Cheng P.,University of Chinese Academy of Sciences | Li Y.,CAS Beijing National Laboratory for Molecular | Zhan X.,Peking University
Energy and Environmental Science | Year: 2014

Indene-C60 bisadduct (ICBA) is used as an electron-cascade acceptor material in poly{4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′] dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b] thiophene-4,6-diyl} (PTB7):[6,6]-phenyl-C71-butyric-acid-methyl-ester (PC 71BM) blend to fabricate ternary blend polymer solar cells (PSCs). Due to higher lowest unoccupied molecular orbital (LUMO) energy levels of ICBA relative to PC71BM, the open circuit voltage (VOC) increases with the addition of ICBA. ICBA plays a bridging role between PTB7 and PC71BM, thus providing more routes for charge transfer at the donor/acceptor (D/A) interface. When the ICBA content is much smaller than the PC71BM content, the morphology of the ternary blend active layer is similar to that of the PTB7:PC71BM blend, which guarantees suitable phase separation and efficient charge transport. Ternary blend devices with 15% ICBA content exhibit an average power conversion efficiency (PCE) of 8.13%, higher than that (7.23%) of the PTB7:PC71BM binary blend. Without any further device work (such as interlayer, invert structure and tandem cells), the ternary blend PSCs exhibit PCEs as high as 8.24%, which is the highest reported for ternary blend PSCs and ICBA-related PSCs. This journal is © the Partner Organisations 2014.


Hao Z.,CAS Beijing National Laboratory for Molecular | Hong S.,CAS Beijing National Laboratory for Molecular | Hong S.,Peking University | Chen X.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Accounts of Chemical Research | Year: 2011

Proteins are the workhorses of the cell, playing crucial roles in virtually every biological process. The revolutionary ability to visualize and monitor proteins in living systems, which is largely the result of the development of green fluorescence protein (GFP) and its derivatives, has dramatically expanded our understanding of protein dynamics and function. Still, GFPs are ill suited in many circumstances; one major drawback is their relatively large size, which can significantly perturb the functions of the native proteins to which they are fused.To bridge this gap, scientists working at the chemistry-biology interface have developed methods to install bioorthogonal functional groups into proteins in living cells. The bioorthogonal group is, by definition, a non-native and nonperturbing chemical group. But more importantly, the installed bioorthogonal handle is able to react with a probe bearing a complementary functionality in a highly selective fashion and with the cell operating in its physiological state. Although extensive efforts have been directed toward the development of bioorthogonal chemical reactions, introducing chemical functionalities into proteins in living systems remains an ongoing challenge. In this Account, we survey recent progress in this area, focusing on a genetic code expansion approach.In nature, a cell uses posttranslational modifications to append the necessary functional groups into proteins that are beyond those contained in the canonical 20 amino acids. Taking lessons from nature, scientists have chosen or engineered certain enzymes to modify target proteins with chemical handles. Alternatively, one can use the cell's translational machinery to genetically encode bioorthogonal functionalities, typically in the form of unnatural amino acids (UAAs), into proteins; this can be done in a residue-specific or a site-specific manner. For studying protein dynamics and function in living cells, site-specific modification by means of genetic code expansion is usually favored.A variety of UAAs bearing bioorthogonal groups as well as other functionalities have been genetically encoded into proteins of interest. Although this approach is well established in bacteria, tagging proteins in mammalian cells is challenging. A facile pyrrolysine-based system, which might potentially become the "one-stop shop" for protein modification in both prokaryotic and eukaryotic cells, has recently emerged. This technology can effectively introduce a series of bioorthogonal handles into proteins in mammalian cells for subsequent chemical conjugation with small-molecule probes. Moreover, the method may provide more precise protein labeling than GFP tagging. These advancements build the foundation for studying more complex cellular processes, such as the dynamics of important receptors on living mammalian cell surfaces. © 2011 American Chemical Society.


Lin Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,University of Chinese Academy of Sciences | Wang J.,Peking University | Zhang Z.-G.,CAS Beijing National Laboratory for Molecular | And 5 more authors.
Advanced Materials | Year: 2015

(Chemical Equation Presented) A novel non-fullerene electron acceptor (ITIC) that overcomes some of the shortcomings of fullerene acceptors, for example, weak absorption in the visible spectral region and limited energy-level variability, is designed and synthesized. Fullerene-free polymer solar cells (PSCs) based on the ITIC acceptor are demonstrated to exhibit power conversion efficiencies of up to 6.8%, a record for fullerene-free PSCs. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.


Cheng P.,CAS Beijing National Laboratory for Molecular | Cheng P.,University of Chinese Academy of Sciences | Ye L.,CAS Beijing National Laboratory for Molecular | Ye L.,University of Chinese Academy of Sciences | And 5 more authors.
Energy and Environmental Science | Year: 2014

Binary additives synergistically boost the power conversion efficiency of all-polymer solar cells up to 3.45%. The nonvolatile additive PDI-2DTT suppresses aggregation of the acceptor PPDIDTT and enhances donor/acceptor mixing, while the additive DIO facilitates aggregation and crystallization of the donor PBDTTT-C-T as well as improves phase separation. Combination of DIO and PDI-2DTT leads to suitable phase separation and improved and balanced charge transport, which is beneficial to efficiency enhancement. This journal is © the Partner Organisations 2014.


Wei D.,CAS Beijing National Laboratory for Molecular | Wei D.,National University of Singapore | Liu Y.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2010

Grapheme, a two-dimensional material, is regarded as one of the most promising candidates for future nanoelectronics due to its atomic thickness, excellent properties and widespread applications. As the first step to investigate its properties and finally to realize the practical applications, graphene must be synthesized in a controllable manner. Thus, controllable synthesis is of great significance, and received more and more attention recently. This Progress Report highlights recent advances in controllable synthesis of graphene, clarifies the problems, and prospects the future development in this field. The applications of the controllable synthesis are also discussed. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gan L.,CAS Beijing National Laboratory for Molecular | Zhang D.,CAS Beijing National Laboratory for Molecular | Guo X.,CAS Beijing National Laboratory for Molecular | Guo X.,Peking University
Small | Year: 2012

Fast and efficient surface functionalization of graphene is achieved by the electrochemical formation of aryl radicals from diazonium salts under mild conditions. Precise control of the ratio of electron-deficient nitro groups to electron-rich amino groups is also demostrated, potentially resulting in the controllable tuning of the electrical properties of graphenes. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Xu C.,CAS Beijing National Laboratory for Molecular | Zhang L.,CAS Beijing National Laboratory for Molecular | Luo S.,CAS Beijing National Laboratory for Molecular
Angewandte Chemie - International Edition | Year: 2014

We describe herein an unprecedented asymmetric α-amination of β-ketocarbonyls under aerobic conditions. The process is enabled by a simple chiral primary amine through the coupling of a catalytic enamine ester intermediate and a nitrosocarbonyl (generated in situ) derived from N-hydroxycarbamate. The reaction features high chemoselectivity and excellent enantioselectivity for a broad range of substrates. Merging O and N: Enantioselective α-amination of β-ketocarbonyl compounds has been achieved by merging enamine catalysis and CuI-catalyzed aerobic oxidation of hydroxycarbamates. Excellent chemoselectivity and enantioselectivity are obtained with the aid of a simple primary/tertiary diamine catalyst. This presents a facile route for the asymmetric synthesis of unnatural amino acids. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Huang Y.,Peking University | Huang Y.,CAS Beijing National Laboratory for Molecular | Liu Z.,Peking University | Liu Z.,CAS Beijing National Laboratory for Molecular
Chemistry - A European Journal | Year: 2013

Specific protein-protein interactions are critical to cellular function. Structural flexibility and disorder-to-order transitions upon binding enable intrinsically disordered proteins (IDPs) to overcome steric restrictions and form complementary binding interfaces, and thus, IDPs are widely considered to have high specificity and low affinity for molecular recognition. However, flexibility may also enable IDPs to form complementary binding interfaces with misbinding partners, resulting in a great number of nonspecific interactions. Consequently, it is questionable whether IDPs really possess high specificity. In this work, we investigated this question from a thermodynamic viewpoint. We collected mutant thermodynamic data for 35 ordered protein complexes and 43 disordered protein complexes. We found that the enthalpy-entropy compensation for disordered protein complexes was more complete than that for ordered protein complexes. We further simulated the binding processes of ordered and disordered protein complexes under mutations. Simulation data confirmed the observation of experimental data analyses and further revealed that disordered protein complexes possessed smaller changes in binding free energy than ordered protein complexes under the same mutation perturbations. Therefore, interactions of IDPs are more malleable than those of ordered proteins due to their structural flexibility in the complex. Our results provide new clues for exploring the relationship between protein flexibility, adaptability, and specificity. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li Y.,CAS Beijing National Laboratory for Molecular | He H.,CAS Beijing National Laboratory for Molecular | Jia X.,CAS Beijing National Laboratory for Molecular | Lu W.-L.,Peking University | And 2 more authors.
Biomaterials | Year: 2012

A pH-sensitive dual-targeting drug carrier (G4-DOX-PEG-Tf-TAM) was synthesized with transferrin (Tf) conjugated on the exterior and Tamoxifen (TAM) in the interior of the fourth generation PAMAM dendrimers for enhancing the blood-brain barrier (BBB) transportation and improving the drug accumulation in the glioma cells. It was found that, on average, 7 doxorubicine (DOX) molecules, over 30 PEG 1000 and PEG 2000 chains and one Tf group were bonded on the periphery of each G4 PAMAM dendrimer, while 29 TAM molecules were encapsulated into the interior of per dendrimer. The pH-triggered DOX release was 32% at pH 4.5 and 6% at pH 7.4, indicating a comparatively fast drug release at weak acidic condition and stable state of the carrier at physiological environment. The in vitro assay of the drug transport across the BBB model showed that G4-DOX-PEG-Tf-TAM exhibited higher BBB transportation ability with the transporting ratio of 6.06% in 3 h. The carrier was internalized into C6 glioma cells upon crossing the BBB model by the coactions of TfR-mediated endocytosis and the inhibition effect of TAM to the drug efflux transports. Moreover, it also displayed the in vitro accumulation of DOX in the avascular C6 glioma spheroids made the tumor volume effectively reduced. © 2012 Elsevier Ltd.


Chen H.,CAS Beijing National Laboratory for Molecular | Guo X.,CAS Beijing National Laboratory for Molecular | Guo X.,Peking University
Small | Year: 2013

Molecular self-assembly is a promising technology for creating reliable functional films in optoelectronic devices with full control of thickness and even spatial resolution. In particular, rationally designed self-assembled monolayers (SAMs) play an important role in modifying the electrode/ semiconductor and semiconductor/dielectric interfaces in field-effect transistors. Carbon nanomaterials, especially single-walled carbon nanotubes and graphene, have attracted intense interest in recent years due to their remarkable physicochemical properties. The combination of the advantages of both SAMs and carbon nanomaterials has been opening up a thriving research field. In this Review article, the unique role of SAMs acting as either active or auxiliary layers in carbon nanomaterials-based field-effect transistors is highlighted for tuning the substrate effect, controlling the carrier type and density in the conducting channel, and even installing new functionalities. The combination of molecular self-assembly and molecular engineering with materials fabrication could incorporate diverse molecular functionalities into electrical nanocircuits, thus speeding the development of nanometer/molecular electronics in the future. The unique role of self-assembled monolayers (SAMs) as either active or auxiliary layers in carbon nanomaterial-based field-effect transistors is highlighted for tuning the substrate effect, controlling the carrier type and density in the conducting channel, and even installing new functionalities. The combination of molecular self-assembly and molecular engineering with materials fabrication could incorporate diverse molecular functionalities into electrical nanocircuits, thus speeding the development of nanometer/molecular electronics in the future. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang X.,Shanghai University | Han K.,Shanghai University | Li J.,Shanghai University | Jia X.,Shanghai University | And 2 more authors.
Polymer Chemistry | Year: 2013

A novel supramolecular alternating copolymer with [c2]daisy-chain dimer and macrocycle host dimer as repeating units has been fabricated. A key factor for this new assembly strategy is based on a [c2]daisy-chain pseudorotaxane bearing additional unbound recognition sites at both ends, which was successfully achieved from a careful designed heterotritopic (AB2-type) copillar[5]arene. By utilizing the intermolecular host-guest interactions between the double-threaded dimer and a pillar[5]arene dimer, a linear supramolecular polymer was prepared. These results provided not only a convenient approach for the construction of [c2]daisy chain based supramolecular polymers, but also a novel method for building supramolecular alternating copolymers. This journal is © The Royal Society of Chemistry.


Xu F.,CAS Beijing National Laboratory for Molecular | Yan D.,Beijing Normal University
Applied Physics Letters | Year: 2011

In this letter, we employ a three-dimensional master equation calculation to investigate the mobility dependence of bulk heterojunction (BHJ) solar cell performance. By taking energetic disorder and morphology into consideration, we show mobility-enhanced device efficiency with a remarkable charge transport loss induced by molecular disorder and an open circuit voltage loss in high mobility region due to morphological defect-assisted bimolecular recombination. The result suggests that the description of interfacial processes is crucial in the modeling of BHJ photovoltaic devices. © 2011 American Institute of Physics.


Li K.,CAS Beijing National Laboratory for Molecular | Ju J.,CAS Beijing National Laboratory for Molecular | Xue Z.,CAS Beijing National Laboratory for Molecular | Ma J.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Nature Communications | Year: 2013

Environmental protection agencies and the petroleum industry require effective methods to separate micron-sized oil droplets from water. However, for most existing separation methods, phase separation occurs in the oil-water mixture. The remaining micron-scale oil droplets, which are not affected by phase separation, are difficult to handle with conventional methods on a large scale because of either a lack of separation ability or drawbacks in throughput capacity. Here we develop an oleophilic array of conical needle structures for the collection of micron-sized oil droplets, inspired by the collection of similar sized water droplets on conical cactus spines. Underwater, these structures mimic cacti and can capture micron-sized oil droplets and continuously transport them towards the base of the conical needles. Materials with this structure show obvious advantages in micron-sized oil collection with high continuity and high throughput. © 2013 Macmillan Publishers Limited.


Li G.,CAS Beijing National Laboratory for Molecular | Zhu D.,CAS Beijing National Laboratory for Molecular | Xue L.,CAS Beijing National Laboratory for Molecular | Jiang H.,CAS Beijing National Laboratory for Molecular | Jiang H.,Beijing Normal University
Organic Letters | Year: 2013

A new pH-responsive fluorescent probe has been reported based on protonation-activable resonance charge transfer. In aqueous solution, probe PQ-Lyso exhibits ratiometric detection of pH changes with a large hypsochromic shift of 76 nm and remarkable changes in the fluorescence intensity ratio (R = F494 nm/F570 nm, R/R0 = 105). Furthermore, PQ-Lyso, which is localized to lysosomes in living cells, can calibrate lysosomal pH using fluorescence ratiometry. © 2013 American Chemical Society.


Ji Q.,CAS Beijing National Laboratory for Molecular | Zheng Y.,CAS Beijing National Laboratory for Molecular | Zheng Y.,Peking University | Zhang Y.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Chemical Society Reviews | Year: 2015

As structural analogues of graphene but with a sizeable band gap, monolayers of group-VIB transition metal dichalcogenides (MX2, M = Mo, W; X = S, Se, Te, etc.) have emerged as the ideal two dimensional prototype for exploring fundamental issues in physics such as valley polarization, and for engineering a wide range of nanoelectronic, optoelectronic and photocatalytic applications. Recently, chemical vapour deposition (CVD) was introduced as a more efficient preparation method than traditional chemical or physical exfoliation options, and has allowed for the successful synthesis of large-area MX2 monolayers possessing a large domain size, high thickness uniformity and continuity, and satisfactory crystal quality. This tutorial review therefore focuses on introducing the more recent advances in the CVD growth of MX2 (MoS2, WS2, MoS2(1-x)Se2xetc.) monolayers via the sulphurisation/decomposition of pre-deposited metal-based precursors, or the one-step reaction and deposition of gaseous metal and chalcogen feedstocks. Differences in growth behaviour caused by commonly used amorphous SiO2/Si, and newly adopted insulating single crystal substrates such as sapphire, mica and SrTiO3, are also comparatively presented. Also discussed are the essential parameters that influence the growth of MX2, such as the temperature, the source-substrate distance and the composition of the carrier gas (Ar/H2). Finally, an assessment is provided for viable future pathways for fine-tuning of the domain size and orientation, thickness uniformity, and the bandgap of MX2 and its alloys. © 2015 The Royal Society of Chemistry.


Jiang F.,Beijing Normal University | Liu J.,Beijing Normal University | Li Y.,Beijing Normal University | Fan L.,Beijing Normal University | And 2 more authors.
Advanced Functional Materials | Year: 2012

A novel catalyst-free synthetic strategy for producing high-quality CdTe nanowires in solution is proposed. A special reaction condition is intentionally constructed in the reaction system to induce the formation of nanowires through oriented in situ assembly of tiny particles. To establish such special synthetic conditions in the CdTe system, not only are its typical features and possible solutions deeply analyzed, but also related factors, such as the ligand environment, injection and growth temperature, and Cd-to-Te precursor ratio, are systemically investigated. High-quality ultralong (up to 10 μm) and ultrathin (less than 10 nm) CdTe nanowires are produced in solution under optimal reaction conditions. Morphological, spectral, and compositional analyses are performed to examine the products formed at different reaction stages in order to clarify the formation mechanism of the CdTe nanowires. Furthermore, the transformation of the CdTe nanowires into CdTe/CdSe core-shell heterostructures is intensively explored, and the CdSe epitaxial growth process is specially tracked by morphological and spectral characterization techniques. Finally, CdTe nanowires coated with a continuous and dense CdSe shell are successfully fabricated by using a proper coating protocol. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wei D.,CAS Beijing National Laboratory for Molecular | Wei D.,National University of Singapore | Wu B.,CAS Beijing National Laboratory for Molecular | Guo Y.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Accounts of Chemical Research | Year: 2013

Because of its atomic thickness, excellent properties, and widespread applications, graphene is regarded as one of the most promising candidate materials for nanoelectronics. The wider use of graphene will require processes that produce this material in a controllable manner. In this Account, we focus on our recent studies of the controllable chemical vapor deposition (CVD) growth of graphene, especially few-layer graphene (FLG), and the applications of this material in electronic devices.CVD provides various means of control over the morphologies of the produced graph ene. We studied several variables that can affect the CVD growth of graphene, including the catalyst, gas flow rate, growth time, and growth temperature and successfully achieved the controlled growth of hexagonal graphene crystals. Moreover, we developed several modified CVD methods for the controlled growth of FLGs. Patterned CVD produced FLGs with desired shapes in required areas. By introducing dopant precursor in the CVD process, we produced substitutionally doped FLGs, avoiding the typically complicated post-treatment processes for graphene doping. We developed a template CVD method to produce FLG ribbons with controllable morphologies on a large scale. An oxidation-activated surface facilitated the CVD growth of polycrystalline graphene without the use of a metal catalyst or a complicated postgrowth transfer process.In devices, CVD offers a controllable means to modulate the electronic properties of the graphene samples and to improve device performance. Using CVD-grown hexagonal graphene crystals as the channel materials in field-effect transistors (FETs), we improved carrier mobility. Substitutional doping of graphene in CVD opened a band gap for efficient FET operation and modulated the Fermi energy level for n-type or p-type features. The similarity between the chemical structure of graphene and organic semiconductors suggests potential applications of graphene in organic devices. We used patterned CVD FLGs as the bottom electrodes in pentacene FETs. The strong π-π interactions between graphene and pentacene produced an excellent interface with low contact resistance and a reduced injection barrier, which dramatically enhances the device performance. We also fabricated reversible nanoelectromechanical (NEM) switches and a logic gate using the FLG ribbons produced using our template CVD method.In summary, CVD provides a controllable means to produce graphene samples with both large area and high quality. We developed several modified CVD methods to produce FLG samples with controlled shape, location, edge, layer, dopant, and growth substrate. As a result, we can modulate the properties of FLGs, which provides materials that could be used in FETs, OFETs, and NEM devices. Despite remarkable advances in this field, further exploration is required to produce consistent, homogeneous graphene samples with single layer, single crystal, and large area for graphene-based electronics. © 2012 American Chemical Society.


Zhang L.,CAS Beijing National Laboratory for Molecular | Fu N.,CAS Beijing National Laboratory for Molecular | Luo S.,CAS Beijing National Laboratory for Molecular
Accounts of Chemical Research | Year: 2015

Conspectus Enantioselective α-functionalizations of carbonyl compounds are fundamental transformations for the asymmetric synthesis of organic compounds. One of the more recent developments along this line is in aminocatalysis, hich leads to the direct α-functionalization of simple aldehydes and ketones. Hoever, most of the advances have been achieved ith linear aldehydes and ketones as substrates. Effective aminocatalysis ith α-branched carbonyls, particularly α-branched ketones, has remained elusive. The primary difficulty arises from the space-demanding α-substituent, hich impedes iminium/enamine formation. In 2005, synthetic organic chemists revived catalysis using primary amines, hich brought ne attention to these challenges, because of the conformational flexibility of primary amines. On the basis of early biomimetic studies by Hine, in 2007 e developed the bioinspired chiral primary amine catalysts featuring primary-tertiary diamines. This type of catalyst involves enamine/iminium catalysis, and e could apply this chemistry to all of the major types of ketones and aldehydes.In this Account, e present research from our laboratory that significantly expands aminocatalysis to include α-branched ketones such as β-ketocarbonyls and α-substituted vinyl ketones. Our primary amine catalysis methodology, hen used alone or in conjunction ith metal catalysts, provides convenient access to both enantiopure α-tertiary and quaternary ketones, structures that are not available via other approaches. Our mechanistic studies shoed that acidic additives play the critical role in facilitating catalytic turnover, most likely by shuttling protons during the enamine/iminium tautomerizations. These additives are also critical to induce the desired stereochemistry via ammonium N-H hydrogen bonding. Proton transfer by shuttling is also stereoselective, resulting in enantioselective enamine protonation as observed in the reactions of α-substituted vinyl ketones. In addition, e have carried out density functional theory studies that help to delineate the origins of the stereoselectivity in these reactions. © 2015 American Chemical Society.


Jiang S.-D.,CAS Beijing National Laboratory for Molecular | Wang B.-W.,CAS Beijing National Laboratory for Molecular | Sun H.-L.,Beijing Normal University | Wang Z.-M.,CAS Beijing National Laboratory for Molecular | Gao S.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2011

An organometallic single-ion magnet is synthesized with only 19 non-hydrogen atoms featuring an erbium ion sandwiched by two different aromatic ligands. This molecule displays a butterfly-shaped hysteresis loop at 1.8 K up to even 5 K. Alternating-current (ac) susceptibility measurement reveals the existence of two thermally activated magnetic relaxation processes with the energy barriers as high as 197 and 323 K, respectively. © 2011 American Chemical Society.


Zhang H.,CAS Institute of Chemistry | Zhang H.,University of Chinese Academy of Sciences | Guo X.,CAS Beijing National Laboratory for Molecular | Guo X.,Peking University | And 4 more authors.
Nano Letters | Year: 2011

Interface modification is an effective and promising route for developing functional organic field-effect transistors (OFETs). In this context, however, researchers have not created a reliable method of functionalizing the interfaces existing in OFETs, although this has been crucial for the technological development of high-performance CMOS circuits. Here, we demonstrate a novel approach that enables us to reversibly photocontrol the carrier density at the interface by using photochromic spiropyran (SP) self-assembled monolayers (SAMs) sandwiched between active semiconductors and gate insulators. Reversible changes in dipole moment of SPs in SAMs triggered by lights with different wavelengths produce two distinct built-in electric fields on the OFET that can modulate the channel conductance and consequently threshold voltage values, thus leading to a low-cost noninvasive memory device. This concept of interface functionalization offers attractive new prospects for the development of organic electronic devices with tailored electronic and other properties. © 2011 American Chemical Society.


Hu F.,CAS Beijing National Laboratory for Molecular | Huang Y.,CAS Beijing National Laboratory for Molecular | Zhang G.,CAS Beijing National Laboratory for Molecular | Zhao R.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Analytical Chemistry | Year: 2014

A new red-emissive bioprobe TPE-red-2AP2H was developed by taking advantage of the unique emission feature of tetraphenylethylene and a cancer cell-specific peptide. By responding to the target protein and the acidic microenvironment of tumor cells, activated fluorescence bioimaging was achieved with high signal-to-noise ratio and without involving mutiple washing steps. Apart from targeting the membrane-anchored LAPTM4B proteins, TPE-red-2AP2H was successfully utilized to trace the intracellular movement of LAPTM4B protein. The generation of 1O2 under visible light irradiation makes this bioprobe also promising for targeted-photodynamic therapy. By discriminating the expression level of the target protein, TPE-red-2AP2H can respond to the progression status of tumors with different photodynamic therapy effect. © 2014 American Chemical Society.


Lin Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,University of Chinese Academy of Sciences | Zhang Z.-G.,CAS Beijing National Laboratory for Molecular | Bai H.,CAS Beijing National Laboratory for Molecular | And 5 more authors.
Energy and Environmental Science | Year: 2015

A nonfullerene electron acceptor (IEIC) based on indaceno[1,2-b:5,6-b′]dithiophene and 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile was designed and synthesized. IEIC exhibited good thermal stability, strong absorption in the 500-750 nm region with an extinction coefficient of 1.1 × 105 M-1 cm-1 at 672 nm, deep LUMO energy level (-3.82 eV) close to those of fullerenes, and a relatively high electron mobility of 2.1 × 10-4 cm2 V-1 s-1. Fullerene-free polymer solar cells (PSCs) based on the blends of the IEIC acceptor and a low-bandgap polymer donor PTB7-TH, using a perylene diimide derivative as a cathode interlayer, showed power conversion efficiencies (PCEs) of up to 6.31%, which is among the best PCEs reported for fullerene-free PSCs. © 2015 The Royal Society of Chemistry.


Sun H.-L.,CAS Beijing National Laboratory for Molecular | Sun H.-L.,Beijing Normal University | Wang Z.-M.,CAS Beijing National Laboratory for Molecular | Gao S.,CAS Beijing National Laboratory for Molecular
Coordination Chemistry Reviews | Year: 2010

Single-chain magnets (SCM) are a novel class of molecular magnetic materials exhibiting slow magnetic relaxation, which arises from large uniaxial type magnetic anisotropy, strong intrachain and very weak or negligible interchain magnetic interactions. Although more than 20 examples of SCM have been reported, the controlled synthesis of SCM is still a challenge. Here we review the three strategies for the construction of SCM, highlight typical examples, discuss the role of intrachain and interchain interactions on the overall magnetic behavior of SCM as well as how to control or tune these interactions. For each strategy we present the advantages/shortcoming and then point out the main directions that remain to be developed in the field. © 2010 Elsevier B.V. All rights reserved.


Peng M.,CAS Beijing National Laboratory for Molecular | Zou D.,CAS Beijing National Laboratory for Molecular | Zou D.,Peking University
Journal of Materials Chemistry A | Year: 2015

Flexible fiber/wire-shaped solar cells are a kind of photovoltaic cell fabricated on wire-like substrates. Fiber-type devices, including inorganic, organic, dye-sensitized and perovskite solar cells, have made great progress in recent years. In particular, the energy conversion efficiency of fiber dye-sensitized solar cells has increased from <0.5% to >9%. In this review, we have provided very detailed insights into the development of various fiber/wire-shaped solar cells, conventional materials, and innovative designs. Particularly, we focused on the properties of fiber dye-sensitized solar cells, innovations for solar energy harvesting, and the integrated power systems for electrochemical energy conversion and storage. Although recent studies only provided the initial ideas, flexible fiber/wire-shaped solar cells facilitated the breakthrough for novel solar architecture and portable/wearable electronics or e-textiles of the future. © The Royal Society of Chemistry.


Hu F.,Beijing Normal University | Zhao Y.S.,CAS Beijing National Laboratory for Molecular
Nanoscale | Year: 2012

Magnetic resonance imaging (MRI) yields high spatially resolved contrast with anatomical details for diagnosis, deeper penetration depth and rapid 3D scanning. To improve imaging sensitivity, adding contrast agents accelerates the relaxation rate of water molecules, thereby greatly increasing the contrast between specific issues or organs of interest. Currently, the majority of T 1 contrast agents are paramagnetic molecular complexes, typically Gd(iii) chelates. Various nanoparticulate T 1 and T 1/T 2 contrast agents have recently been investigated as novel agents possessing the advantages of both the T 1 contrast effect and nanostructural characteristics. In this minireview, we describe the recent progress of these inorganic nanoparticle-based MRI contrast agents. Specifically, we mainly report on Gd and Mn-based inorganic nanoparticles and ultrasmall iron oxide/ferrite nanoparticles. This journal is © 2012 The Royal Society of Chemistry.


Rui H.,Peking University | Xing R.,Peking University | Xu Z.,Brown University | Xu Z.,Massachusetts Institute of Technology | And 3 more authors.
Advanced Materials | Year: 2010

Synthesis of multifunctional magnetic nanoparticles (MFMNPs) is one of the most active research areas in advanced materials. MFMNPs that have magnetic properties and other functionalities have been demonstrated to show great promise as multimodality imaging probes. Their multifunctional surfaces also allow rational conjugations of biological and drug molecules, making it possible to achieve target-specific diagnostics and therapeutics. This review first outlines the synthesis of MNPs of metal oxides and alloys and then focuses on recent developments in the fabrication of MFMNPs of core/shell, dumbbell, and composite hybrid type. It also summarizes the general strategies applied for NP surface functionalization. The review further highlights some exciting examples of these MFMNPs for multimodality imaging and for target-specific drug/gene delivery applications. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhong Y.,CAS Beijing National Laboratory for Molecular | Tian G.,CAS Institute of High Energy Physics | Tian G.,University of Sichuan | Gu Z.,CAS Institute of High Energy Physics | And 6 more authors.
Advanced Materials | Year: 2014

Nd3+-sensitized quenching-shield sandwich-structured upconversion nanoparticles are reported, which exhibit highly efficient upconversion photoluminescence under excitation by an 800 nm continuous-wave laser. The transition-layer structure is essential to bridge energy transfer from the sensitizer to the activator and simultaneously block energy back-transfer from the activator to the sensitizer. These 800 nm-excited upconversion nanoparticles are a key step toward the development of upconversion nanophosphors for biological applications. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cao M.,Beihang University | Ju J.,CAS Beijing National Laboratory for Molecular | Li K.,CAS Beijing National Laboratory for Molecular | Dou S.,University of Wollongong | And 2 more authors.
Advanced Functional Materials | Year: 2014

Although clean drinking water is a basic human need, freshwater scarcity has been identified as a major global problem of the 21st century. Nature has long served as a source of inspiration for human beings to develop new technology. The cactus in the desert possesses a multifunctional integrated fog collection system originating from the cooperation of a Laplace pressure gradient and the wettability difference. In this contribution, inspired by the cactus, an artificial fog collector on a large scale is first fabricated through integrating cactus spine-like hydrophobic conical micro-tip arrays with the hydrophilic cotton matrix. The novel cactus-inspired fog collector can spontaneously and continuously collect, transport, and preserve fog water, demonstrating high fog collection efficiency and promising applications in the regions with drinking water scarcity. Furthermore, the present approach is simple, time-saving and cost-effective, which provides a potential device and new idea to solve the global water crisis. Inspired by the fog-harvesting behavior of the cactus, a novel fog collector in large scale is first fabricated through integrating cactus spine-like hydrophobic conical micro-tip arrays with a hydrophilic cotton matrix, which can spontaneously and continuously collect, transport, and preserve fog water. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Garner D.K.,University of Illinois at Urbana - Champaign | Liang L.,CAS Beijing National Laboratory for Molecular | Barrios D.A.,University of Illinois at Urbana - Champaign | Zhang J.-L.,CAS Beijing National Laboratory for Molecular | Lu Y.,University of Illinois at Urbana - Champaign
ACS Catalysis | Year: 2011

Two questions important to the success in metalloenzyme design are how to attach or anchor metal cofactors inside protein scaffolds and in what way such positioning affects enzymatic properties. We have previously reported a dual anchoring method to position a nonnative cofactor, MnSalen (1), inside the heme cavity of apo sperm whale myoglobin (Mb) and showed that the dual anchoring can increase both the activity and enantioselectivity over single anchoring methods, making this artificial enzyme an ideal system to address the above questions. Here, we report systematic investigations of the effect of different covalent attachment or anchoring positions on reactivity and selectivity of sulfoxidation by the MnSalen-containing Mb enzymes. We have found that changing the left anchor from Y103C to T39C has an almost identical effect of increasing rate by 1.8-fold and increasing selectivity by +15% for S, whether the right anchor is L72C or S108C. At the same time, regardless of the identity of the left anchor, changing the right anchor from S108C to L72C increases the rate by 4-fold and selectivity by +66%. The right anchor site was observed to have a greater influence than the left anchor site on the reactivity and selectivity in sulfoxidation of a wide scope of other ortho-, meta- and para-substituted substrates. The 1 ·Mb(T39C/L72C) showed the highest reactivity (TON up to 2.32 min-1) and selectivity (ee % up to 83%) among the different anchoring positions examined. Molecular dynamic simulations indicate that these changes in reactivity and selectivity may be due to the steric effects of the linker arms inside the protein cavity. These results indicate that small differences in the anchor positions can result in significant changes in reactivity and enantioselectivity, probably through steric interactions with substrates when they enter the substrate-binding pocket, and that the effects of right and left anchor positions are independent and additive in nature. The finding that the anchoring arms can influence both the positioning of the cofactor and steric control of substrate entrance will help design better functional metalloenzymes with predicted catalytic activity and selectivity. © 2011 American Chemical Society.


Gu J.,CAS Beijing National Laboratory for Molecular | Zhang Y.-W.,CAS Beijing National Laboratory for Molecular | Tao F.,University of Notre Dame
Chemical Society Reviews | Year: 2012

Synthesis of bimetallic nanomaterials with well controlled shape is an important topic in heterogeneous catalysis, low-temperature fuel cell technology, and many other fields. Compared with monometallic counterparts, bimetallic nanocatalysts endow scientists with more opportunities to optimize the catalytic performance by modulating the charge transfer between different metals, local coordination environment, lattice strain and surface element distribution. Considering the current challenges in shape controlled synthesis of bimetallic nanocatalysts, this tutorial review highlights some significant achievements in preparing bimetallic alloy, core-shell and heterostructure nanocrystals with well-defined morphologies, summarizes four general routes and some key factors of the bimetallic shape control scenarios, and provides some general ideas on how to design synthetic strategies to control the shape and exposing facets of bimetallic nanocrystals. The composition and shape dependent catalytic behaviours of bimetallic nanocrystals are reviewed as well. © 2012 The Royal Society of Chemistry.


Jiang L.,CAS Institute of Physics | Yang T.,CAS Institute of Physics | Liu F.,Sun Yat Sen University | Dong J.,Tsinghua University | And 6 more authors.
Advanced Materials | Year: 2013

Large-scale, uniform, vertically standing graphene with atomically thin edges are controllably synthesized on copper foil using a microwave-plasma chemical vapor deposition system. A growth mechanism for this system is proposed. This film shows excellent field-emission properties, with low turn-on field of 1.3 V μm-1, low threshold field of 3.0 V μm -1 and a large field-enhancement factor more than 10 000. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li A.D.Q.,Washington State University | Zhan C.,CAS Beijing National Laboratory for Molecular | Hu D.,Pacific Northwest National Laboratory | Wan W.,Washington State University | Yao J.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2011

A single probe has limited brightness in time-domain imaging and such limitation frequently renders individual molecules undetectable in the presence of interference or complex cellular structures. However, a single photoswitchable probe produces a signal, which can be separated from interference or noise using photoswitching-enabled Fourier transformation (PFT). As a result, the light-modulated probes can be made super bright in the frequency domain simply by acquiring more cycles in the time domain. © 2011 American Chemical Society.


Van Franeker J.J.,TU Eindhoven | Turbiez M.,TU Eindhoven | Turbiez M.,Dutch Polymer Institute | Li W.,BASF | And 4 more authors.
Nature Communications | Year: 2015

The photoactive layer of organic solar cells consists of a nanoscale blend of electron-donating and electron-accepting organic semiconductors. Controlling the degree of phase separation between these components is crucial to reach efficient solar cells. In solution-processed polymer-fullerene solar cells, small amounts of co-solvents are commonly used to avoid the formation of undesired large fullerene domains that reduce performance. There is an ongoing discussion about the origin of this effect. To clarify the role of co-solvents, we combine three optical measurements to investigate layer thickness, phase separation and polymer aggregation in real time during solvent evaporation under realistic processing conditions. Without co-solvent, large fullerene-rich domains form via liquid-liquid phase separation at ∼20 vol% solid content. Under such supersaturated conditions, co-solvents induce polymer aggregation below 20 vol% solids and prevent the formation of large domains. This rationalizes the formation of intimately mixed films that give high-efficient solar cells for the materials studied. © 2015 Macmillan Publishers Limited. All rights reserved.


Liu L.,CAS Beijing National Laboratory for Molecular | Chen J.,University of Wollongong | Wang S.,CAS Beijing National Laboratory for Molecular
Advanced Healthcare Materials | Year: 2013

A flexible and transparent anti-bacterial film is prepared by depositing polyterthiophene incorporating porphyrin onto the poly(ethylene terephthalate) sheet by a simple and rapid oxidation polymerization method. The film can generate singlet oxygen by FRET from polyterthiophene to porphyrin to effectively kill the adsorbed bacteria under white light. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cao C.-Y.,CAS Beijing National Laboratory for Molecular | Cao C.-Y.,Harbin Institute of Technology | Guo W.,CAS Beijing National Laboratory for Molecular | Cui Z.-M.,Beihang University | And 2 more authors.
Journal of Materials Chemistry | Year: 2011

A rapid method based on an efficient gas/liquid interfacial microwave-assisted process has been developed to synthesize flowerlike NiO hollow nanosphere precursors, which were then transformed to NiO by simple calcinations. The wall of the sphere is composed of twisted NiO nanosheets that intercalated with each other. Such hollow structure is different from widely reported flowerlike nanostructures with solid cores. An Ostwald ripening mechanism was proposed for the formation of the hollow nanostructures. The products were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution TEM, energy-dispersive X-ray analysis, and N2 adsorption-desorption methods. These flowerlike NiO hollow nanospheres have high surface area of 176 m2 g-1. Electrochemical properties show a high specific capacitance of 585 F g-1 at a discharge current of 5 A g-1 and excellent cycling stability, suggesting its promising potentials in supercapacitors. © The Royal Society of Chemistry 2011.


Cui Z.-M.,Beihang University | Chen Z.,CAS Beijing National Laboratory for Molecular | Cao C.-Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University | And 2 more authors.
Chemical Communications | Year: 2013

Through a simple polymeric carbon assisted method, a yolk-shell structured Fe2O3@mesoporous SiO2 nanoreactor was synthesized and showed excellent activity in Fenton-like reactions toward methylene blue total degradation. This journal is © The Royal Society of Chemistry.


Wen L.,CAS Beijing National Laboratory for Molecular | Hou X.,CAS National Center for Nanoscience and Technology | Tian Y.,CAS Beijing National Laboratory for Molecular | Zhai J.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2010

Inspired by the light-driven, cross-membrane proton pump of biological systems, a photoelectric conversion system based on a smart-gating, protondriven nanochannel is constructed. In this system, solar energy is the only source of cross-membrane proton motive force that induces a diffusion potential and photocurrent flowing through the external circuit. Although the obtained photoelectric conversion performance is lower than that of conventional solid photovoltaic devices, it is believed that higher efficiencies can be generated by enhancing the protonation capacity of the photo-acid molecules, optimizing the membrane, and synthesizing high-performance photosensitive molecules. This type of facile and environmentally friendly photoelectric conversion has potential applications for future energy demands such as the production of power for in vivo medical devices. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gao J.,CAS Beijing National Laboratory for Molecular | Guo W.,CAS Beijing National Laboratory for Molecular | Guo W.,CAS Technical Institute of Physics and Chemistry | Feng D.,Fudan University | And 3 more authors.
Journal of the American Chemical Society | Year: 2014

Salinity difference between seawater and river water is a sustainable energy resource that catches eyes of the public and the investors in the background of energy crisis. To capture this energy, interdisciplinary efforts from chemistry, materials science, environmental science, and nanotechnology have been made to create efficient and economically viable energy conversion methods and materials. Beyond conventional membrane-based processes, technological breakthroughs in harvesting salinity gradient power from natural waters are expected to emerge from the novel fluidic transport phenomena on the nanoscale. A major challenge toward real-world applications is to extrapolate existing single-channel devices to macroscopic materials. Here, we report a membrane-scale nanofluidic device with asymmetric structure, chemical composition, and surface charge polarity, termed ionic diode membrane (IDM), for harvesting electric power from salinity gradient. The IDM comprises heterojunctions between mesoporous carbon (pore size ∼7 nm, negatively charged) and macroporous alumina (pore size ∼80 nm, positively charged). The meso-/macroporous membrane rectifies the ionic current with distinctly high ratio of ca. 450 and keeps on rectifying in high-concentration electrolytes, even in saturated solution. The selective and rectified ion transport furthermore sheds light on salinity-gradient power generation. By mixing artificial seawater and river water through the IDM, substantially high power density of up to 3.46 W/m2 is discovered, which largely outperforms some commercial ion-exchange membranes. A theoretical model based on coupled Poisson and Nernst-Planck equations is established to quantitatively explain the experimental observations and get insights into the underlying mechanism. The macroscopic and asymmetric nanofluidic structure anticipates wide potentials for sustainable power generation, water purification, and desalination. © 2014 American Chemical Society.


Chen Z.,CAS Beijing National Laboratory for Molecular | Cui Z.-M.,Beihang University | Niu F.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University | Song W.-G.,CAS Beijing National Laboratory for Molecular
Chemical Communications | Year: 2010

A true nanoreactor composed of mesoporous silica hollow spheres and Pd nanoparticles residing inside the spheres shows superior activity in Suzuki coupling reactions with 99.5% yield in 3 min. © 2010 The Royal Society of Chemistry.


Zhang Z.,CAS Beijing National Laboratory for Molecular | Chen G.,CAS Beijing National Laboratory for Molecular | Wang H.,National Center for Nanosciences and Technology of China | Zhai W.,CAS Ningbo Institute of Material Technology and Engineering
Journal of Materials Chemistry C | Year: 2015

A new strategy, i.e. interfacial adsorption-soft template polymerization, is developed to enhance polymer thermoelectric property. The obtained nanocomposite 3D interconnected architecture consisting of reduced graphene oxide (rGO) nanolayers sandwiched by polypyrrole (PPy) nanowires is directly confirmed by scanning and transmission electron microscopies. Moreover, the nanocomposites reveal significantly enhanced thermoelectric performance. At rGO : PPy ratio of 50 wt%, the nanocomposite power factor reaches ∼476.1 times that of pure PPy nanowires. Our results suggest that a greatly enhanced thermoelectric property for polymer nanocomposites can be achieved by a complex morphology design. © 2015 The Royal Society of Chemistry.


Wu Y.,CAS Beijing National Laboratory for Molecular | Chen X.,Beihang University | Su B.,CAS Beijing National Laboratory for Molecular | Song Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2012

Bead-shaped 1D structures are of great interest due to their unique applications in mesoscopic optics/electronics and their specific ability to collect tiny droplets. Here, a novel method to fabricate aligning bead-shaped nanowire arrays assisted by highly adhesive superhydrophobic surfaces based on a micropillar guiding strategy is presented. Different from previous fabrication techniques, bead-shaped nanowires generated in this method are strictly oriented in a large scale. Rayleigh instability, which occurs at ultralow polymer concentration, can introduce bead-shaped nanowires at the cost of structural strength. Thus, PS spheres are more suitable to serve as bead building blocks to generate firm bead-shaped nanowire arrays. The bead number is tunable by tailoring the polystyrene-sphere/polyvinyl-formal ratio. Furthermore, as-prepared bead-shaped nanowires have the unique ability to directionally drive tiny drops and collect coalesced microdroplets when placed in mist. With an increase in humidity, the nanowires show a segmented swelling behavior in the "bead" parts whereas the "joint nanowire" parts remain the same. Because such bead-shaped nanowires are formed regularly, collected microdroplets upon the beads would not interact with each other. The findings offer new insight into the alignment of bead-shaped nanostructures and might provide promising opportunities in fundamental research and for industrial applications. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu K.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
ACS Nano | Year: 2011

Nature is a school for human beings. Learning from nature has long been a source of bioinspiration for scientists and engineers. Multiscale structures are characteristic for biological materials, exhibiting inherent multifunctional integration. Optimized biological solutions provide inspiration for scientists and engineers to design and to fabricate multiscale structured materials for multifunctional integration. © 2011 American Chemical Society.


Yang M.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular | Chen P.R.,CAS Beijing National Laboratory for Molecular | Chen P.R.,Peking Tsinghua Center for Life science
Chemical Society Reviews | Year: 2014

Considerable attention has been focused on improving the biocompatibility of Cu(i)-catalyzed azide-alkyne cycloaddition (CuAAC), a hallmark of bioorthogonal reaction, in living cells. Besides creating copper-free versions of click chemistry such as strain promoted azide-alkyne cycloaddition (SPAAC), a central effort has also been made to develop various Cu(i) ligands that can prevent the cytotoxicity of Cu(i) ions while accelerating the CuAAC reaction. Meanwhile, additional transition metals such as palladium have been explored as alternative sources to promote a bioorthogonal conjugation reaction on cell surface, as well as within an intracellular environment. Furthermore, transition metal mediated chemical conversions beyond conjugation have also been utilized to manipulate protein activity within living systems. We highlight these emerging examples that significantly enriched our protein chemistry toolkit, which will likely expand our view on the definition and applications of bioorthogonal chemistry. © 2014 the Partner Organisations.


Liu K.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Annual Review of Materials Research | Year: 2012

Self-cleaning surfaces have drawn a lot of interest for both fundamental research and practical applications. This review focuses on the recent progress in mechanism, preparation, and application of self-cleaning surfaces. To date, self-cleaning has been demonstrated by the following four conceptual approaches: (a) TiO2-based superhydrophilic self-cleaning, (b) lotus effect self-cleaning (superhydrophobicity with a small sliding angle), (c) gecko setaeinspired self-cleaning, and (d) underwater organismsinspired antifouling self-cleaning. Although a number of self-cleaning products have been commercialized, the remaining challenges and future outlook of self-cleaning surfaces are also briefly addressed. Through evolution, nature, which has long been a source of inspiration for scientists and engineers, has arrived at what is optimal. We hope this review will stimulate interdisciplinary collaboration among material science, chemistry, biology, physics, nanoscience, engineering, etc., which is essential for the rational design and reproducible construction of bio-inspired multifunctional self-cleaning surfaces in practical applications. © Copyright ©2012 by Annual Reviews. All rights reserved.


Su B.,CAS Beijing National Laboratory for Molecular | Guo W.,CAS Beijing National Laboratory for Molecular | Guo W.,CAS Technical Institute of Physics and Chemistry | Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
Small | Year: 2015

In this Review, nature-inspired binary cooperative complementary nanomaterials (BCCNMs), consisting of two components with entirely opposite physiochemical properties at the nanoscale, are presented as a novel concept for the building of promising materials. Once the distance between the two nanoscopic components is comparable to the characteristic length of some physical interactions, the cooperation between these complementary building blocks becomes dominant and endows the macroscopic materials with novel and superior properties. The first implementation of the BCCNMs is the design of bio-inspired smart materials with superwettability and their reversible switching between different wetting states in response to various kinds of external stimuli. Coincidentally, recent studies on other types of functional nanomaterials contribute more examples to support the idea of BCCNMs, which suggests a potential yet comprehensive range of future applications in both materials science and engineering. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ju J.,CAS Beijing National Laboratory for Molecular | Zheng Y.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
Accounts of Chemical Research | Year: 2014

ConspectusOne-dimensional materials (1D) capable of transporting liquid droplets directionally, such as spider silks and cactus spines, have recently been gathering scientists attention due to their potential applications in microfluidics, textile dyeing, filtration, and smog removal. This remarkable property comes from the arrangement of the micro- and nanostructures on these organisms surfaces, which have inspired chemists to develop methods to prepare surfaces with similar directional liquid transport ability. In this Account, we report our recent progress in understanding how this directional transport works, as well our advances in the design and fabrication of bioinspired 1D materials capable of transporting liquid droplets directionally.To begin, we first discuss some basic theories on droplet directional movement. Then, we discuss the mechanism of directional transport of water droplets on natural spider silks. Upon contact with water droplets, the spider silk undergoes what is known as a wet-rebuilt, which forms periodic spindle-knots and joints. We found that the resulting gradient of Laplace pressure and surface free energy between the spindle-knots and joints account for the cooperative driving forces to transport water droplets directionally. Next, we discuss the directional transport of water droplets on desert cactus. The integration of multilevel structures of the cactus and the resulting integration of multiple functions together allow the cactus spine to transport water droplets continuously from tip to base.Based on our studies of natural spider silks and cactus spines, we have prepared a series of artificial spider silks (A-SSs) and artificial cactus spines (A-CSs) with various methods. By changing the surface roughness and chemical compositions of the artificial spider silks spindle-knots, or by introducing stimulus-responsive molecules, such as thermal-responsive and photoresponsive molecules, onto the spindle-knots, we can reversibly manipulate the direction of water droplets movement on the prepared A-SSs. In addition, the A-SSs with nonuniform spindle-knots, such as multilevel sized spindle-knots and gradient spindle-knots, further demonstrate integrated directional transport ability for water droplets. Through mimicking the main principle of cactus spines in transporting water droplets, we were able to fabricate both single and array A-CSs, which are able to transport liquid droplets directionally both in air and under water.Lastly, we demonstrated some applications of this directional liquid transport, from aspects of efficient fog collection to oil/water separation. In addition, we showed some potential applications in smart catalysis, tracer substance enrichment, smog removal, and drug delivery. © 2014 American Chemical Society.


Liu K.,Beihang University | Tian Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Beijing National Laboratory for Molecular
Progress in Materials Science | Year: 2012

Through evolution, nature has arrived at what is optimal. Inspired by the biomaterials with special wettability, superhydrophobic materials have been well-investigated and -covered by several excellent reviews. The construction of superoleophobicity is more difficult than that of superhydrophobicity because the surface tension of oil or other organic liquids is lower than that of water. However, superoleophobic surfaces have drawn a great deal of attention for both fundamental research and practical applications in a variety of fields. In this contribution, we focus on recent research progress in the design, fabrication, and application of bio-inspired superoleophobic and smart surfaces, including superoleophobic-superhydrophobic surfaces, oleophobic-hydrophilic surfaces, underwater superoleophobic surfaces, and smart surfaces. Although the research of bio-inspired superoleophobicity is in its infancy, it is a rapidly growing and enormously promising field. The remaining challenges and future outlook of this field are also addressed. Multifunctional integration is a inherent characteristic for biological materials. Learning from nature has long been a source of bio-inspiration for scientists and engineers. Therefore, further cross-disciplinary cooperation is essential for the construction of multifunctional advanced superoleophobic surfaces through learning the optimized biological solutions from nature. We hope this review will provide some inspirations to the researchers in the field of material science, chemistry, physics, biology, and engineering. © 2012 Elsevier Ltd. All rights reserved.


Tian D.,Beihang University | Zhai J.,Beihang University | Song Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
Advanced Functional Materials | Year: 2011

Surface wettability as a response to the cooperation of different stimuli has been intensively studied and provides more advantages than as a response to a single stimulus. Recently, we demonstrated the patterned wettability transition from the Cassie to the Wenzel state on a superhydrophobic aligned-ZnO-nanorod array surface via a photoelectric cooperative wetting process. However, the specific aligned-nanorod array structure of such devices is easily damaged due to their low mechanical strength and cannot sustain multiple transfer printing. Meanwhile, the patterned wetting process is not easily controlled due to the air-permeable structure of adjacent nanorods. As a result, in practice, it is difficult to apply liquid reprography on such a nanostructure. Here, we demonstrate photoelectric cooperative induced patterned wetting on the superhydrophobic aligned-nanopore array surface of TiO 2-coated nanoporous AAO film, which has a high mechanical strength and excellent controllability. Liquid reprography is achieved through the patterned wetting process on the superhydrophobic aligned-nanopore array surface, which is a new progression in liquid reprography, and is promising for gearing up the application of photoelectric cooperative liquid reprography. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang L.,CAS Beijing National Laboratory for Molecular | Zhao Y.,Beihang University | Tian Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Technical Institute of Physics and Chemistry | Jiang L.,Beihang University
Angewandte Chemie - International Edition | Year: 2015

Oil/water separation membranes with different wettability towards water are attractive for their economic efficiency and convenience. The key factor for the separation process is the roughness-enhanced wettability of membranes based on the intrinsic wetting threshold (IWT) of water, that is, the limitation of the wettability caused by hydrophobicity and hydrophilicity. However, the separation of organic liquids (OLs) remains a challenge. Herein, we manipulate the surface tensions of nanofibrous membranes to lie between the IWTs of the two OLs to be separated so that the nanofibrous membranes can be endowed with superlyophobicity and superlyophilicity for the two liquids, and thus lead to successful separation. Our investigations provide a general strategy to separate any immiscible liquids efficiently, and may lead to the development of membranes with a large capacity, high flux, and high selectivity for organic reactions or liquid extraction in chemical engineering. Going separate ways: The surface tensions of nanofibrous membranes have been manipulated to lie in between the intrinsic wetting thresholds (IWTs) of the two organic liquids to be separated. This endows the nanofibrous membranes with superlyophobicity and superlyophilicity for the two liquids, respectively, and thus leads to a successful separation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu N.,Huazhong University of Science and Technology | Jiang Y.,Beihang University | Zhou Y.,CAS Beijing National Laboratory for Molecular | Xia F.,Huazhong University of Science and Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2013

Pore me another one: Sub-nanomolar sequence-specific DNA detection and sub-micromolar small-molecule (ATP) detection was shown by way of self-assembly and disassembly of DNA superstructures within solid-state nanopores (see scheme). These DNA structures provide a built-in amplification mechanism to increase the signal strength and sensitivity. This sensor was also shown to work within complex mixtures, such as mammalian serum. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Su B.,CAS Beijing National Laboratory for Molecular | Wang S.,CAS Beijing National Laboratory for Molecular | Wu Y.,CAS Beijing National Laboratory for Molecular | Chen X.,Beihang University | And 2 more authors.
Advanced Materials | Year: 2012

Elaborately programmed fluorescent calcein nanowire arrays can be prepared with the aid of superhydrophobic pillar-structured surfaces with high adhesion. Each nanowire can be precisely positioned by well designed tip-structured micropillars, indicating an advance in the methodologies of controlling small molecular 1D organic nanostructures. The as-prepared fluorescent nanowire arrays can serve as a ferrous salt sensing device. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Bai H.,CAS National Center for Nanoscience and Technology | Bai H.,University of Chinese Academy of Sciences | Ju J.,CAS Beijing National Laboratory for Molecular | Ju J.,University of Chinese Academy of Sciences | And 2 more authors.
Advanced Materials | Year: 2012

Spider silk has been an attractive biopolymer since ancient times. Learning from both its excellent properties and spinning process, silk provides people with inspiration to develop functional fibers. Recently, inspired by shiny water droplets on a spider's web, we revealed that the capture silk of the cribellate spider would deform to have a special periodic spindle-knots structure and hence displayed unique wettability, making it efficient at directional water-collecting. This provides insights in designing functional fibers with unique wettability, by either creating special structures on the fiber surface, or modifying it with responsive molecules. These bioinspired functional fibers may find applications in many fields, such as water collection, smart catalysis, filtration, and sensing. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yang N.,Beihang University | Yang N.,CAS Institute of Process Engineering | Zhai J.,Beihang University | Zhai J.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
ACS Nano | Year: 2010

As a novel two-dimensional (2D) material, graphene shows great benefits in electric and material science. Compared to 1D nanomaterials, it may show more excellent properties. Here, we introduced graphene as 2D bridges into the nanocrystalline electrodes of dye-sensitized solar cells, which brought a faster electron transport and a lower recombination, together with a higher light scattering. On the basis of these advantages, the short-circuit current density was increased by 45% without sacrificing the open-circuit voltage, and the total conversion efficiency was 6.97%, which was increased by 39%, comparing with the nanocrystalline titanium dioxide photoanode, and it was also much better than the 1D nanomaterial composite electrode. © 2010 American Chemical Society.


Chen X.,Beihang University | Wu Y.,CAS Beijing National Laboratory for Molecular | Su B.,CAS Beijing National Laboratory for Molecular | Wang J.,Beihang University | And 2 more authors.
Advanced Materials | Year: 2012

Marine methane bubbles are absorbed, steadily stored, and continuously transported based on the employment of superhydrophobic sponges. Antiwetting sponges are water-repellent in the atmosphere and absorb gas bubbles under water. Their capacity to store methane bubbles increases with enhanced submerged depth. Significantly, trapped methane bubbles can be continuously transported driven by differential pressure. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Su B.,CAS Beijing National Laboratory for Molecular | Wang S.,CAS Beijing National Laboratory for Molecular | Ma J.,CAS Beijing National Laboratory for Molecular | Wu Y.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Advanced Materials | Year: 2012

Elaborate positioning of nanowire arrays can be generated upon highly adhesive superhydrophobic pillar-structured silicon substrates. The site of each nanowire can be precisely positioned by well designed tip-structured micropillars, yielding on-demand nanowire patterns. This approach might affect existing applications and enable new opportunities in organically functional devices and bio/chemical sensors. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu K.,Beihang University | Du J.,Beihang University | Wu J.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Nanoscale | Year: 2012

Functional integration is an inherent characteristic for multiscale structures of biological materials. In this contribution, we first investigate the liquid-solid adhesive forces between water droplets and superhydrophobic gecko feet using a high-sensitivity micro-electromechanical balance system. It was found, in addition to the well-known solid-solid adhesion, the gecko foot, with a multiscale structure, possesses both superhydrophobic functionality and a high adhesive force towards water. The origin of the high adhesive forces of gecko feet to water could be attributed to the high density nanopillars that contact the water. Inspired by this, polyimide films with gecko-like multiscale structures were constructed by using anodic aluminum oxide templates, exhibiting superhydrophobicity and a strong adhesive force towards water. The static water contact angle is larger than 150° and the adhesive force to water is about 66 μN. The resultant gecko-inspired polyimide film can be used as a "mechanical hand" to snatch micro-liter liquids. We expect this work will provide the inspiration to reveal the mechanism of the high-adhesive superhydrophobic of geckos and extend the practical applications of polyimide materials. © 2012 The Royal Society of Chemistry.


Tian Y.,CAS Beijing National Laboratory for Molecular | Su B.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
Advanced Materials | Year: 2014

Engineering the wettability of solid materials is a traditional, yet key issue in surface science and attracts tremendous interest by researchers in diverse fields. Recently, different superwetting phenomena have been discovered in both nature and experimental results. Therefore, in this review, various superwetting states, leading to a "superwettability" system, are summarized and predicted. Fundamental rules for understanding superwettability are discussed, mainly taking superhydrophobicity in air as an example. Then, some recent application progress of individual members of this "superwettability" system are introduced. Notably, several novel application fields, mainly gas, water, oil and/or other liquid environments, are presented in the following section. By combining different members of this "superwettability" system, new interfacial functions can be generated, allowing unexpected applications, such as in environmental protection, energy, green industry, and many other important domains. Finally, the future development of this interesting "superwettability" system is discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jiang Y.,Beihang University | Liu N.,Huazhong University of Science and Technology | Guo W.,CAS Beijing National Laboratory for Molecular | Xia F.,Huazhong University of Science and Technology | And 2 more authors.
Journal of the American Chemical Society | Year: 2012

Integrating biological components into artificial devices establishes an interface to understand and imitate the superior functionalities of the living systems. One challenge in developing biohybrid nanosystems mimicking the gating function of the biological ion channels is to enhance the gating efficiency of the man-made systems. Herein, we demonstrate a DNA supersandwich and ATP gated nanofluidic device that exhibits high ON-OFF ratios (up to 106) and a perfect electric seal at its closed state (∼Gω). The ON-OFF ratio is distinctly higher than existing chemically modified nanofluidic gating systems. The gigaohm seal is comparable with that required in ion channel electrophysiological recording and some lipid bilayer-coated nanopore sensors. The gating function is implemented by self-assembling DNA supersandwich structures into solid-state nanochannels (open-to-closed) and their disassembly through ATP-DNA binding interactions (closed-to-open). On the basis of the reversible and all-or-none electrochemical switching properties, we further achieve the IMPLICATION logic operations within the nanofluidic structures. The present biohybrid nanofluidic device translates molecular events into electrical signals and indicates a built-in signal amplification mechanism for future nanofluidic biosensing and modular DNA computing on solid-state substrates. © 2012 American Chemical Society.


Liu K.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Nanoscale | Year: 2011

Metals are important and irreplaceable engineered materials in our society. Nature is a school for scientists and engineers, which has long served as a source of inspiration for humans. Inspired by nature, a variety of metallic surfaces with special wettability have been fabricated in recent years through the combination of surface micro- and nanostructures and chemical composition. These metallic surfaces with special wettability exhibit important applications in anti-corrosion, microfluidic systems, oil-water separation, liquid transportation, and other fields. Recent achievements in the fabrication and application of metallic surfaces with special wettability are presented in this review. The research prospects and directions of this field are also briefly addressed. We hope this review will be beneficial to expand the practical applications of metals and offer some inspirations to the researchers in the fields of engineering, biomedicine, and materials science. © 2011 The Royal Society of Chemistry.


Liu M.,CAS Beijing National Laboratory for Molecular | Xue Z.,CAS Beijing National Laboratory for Molecular | Liu H.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Angewandte Chemie - International Edition | Year: 2012

Interfacial phenomena: A solid-phase-independent strategy for tuning the surface wettability is presented. Lewis acid-base interactions at the oil-water interface can greatly decrease the liquid-liquid interfacial tension and induce oleophilic to superoleophobic wetting transition on a nonresponsive microstructured surface (see picture). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang J.,Beihang University | Lin L.,CAS Beijing National Laboratory for Molecular | Cheng Q.,Beihang University | Jiang L.,Beihang University
Angewandte Chemie - International Edition | Year: 2012

Inspired by nacre, a layered poly(N-isopropylacrylamide)-clay nanocomposite hydrogel was successfully fabricated by combination of vacuum-filtration self-assembly and photo-initiated in situ polymerization. This bio-inspired layered nanocomposite hydrogel shows excellent mechanical properties, which can rival some biological soft tissues (see picture). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Diao P.,Beihang University | Liu Z.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2010

Single-walled carbon nanotubes (SWNTs), as one of the most promising one-dimension nanomaterials due to its unique structure, peculiar chemical, mechanical, thermal, and electronic properties, have long been considered as an important building block to construct ordered alignments. Vertically aligned SWNTs (v-SWNTs) have been successfully prepared by using direct growth and chemical assembly strategies. In this review, we focus explicitly on the v-SWNTs fabricated via chemical assembly strategy. We provide the readers with a full and systematic summary covering the advances in all aspects of this area, including various approaches for the preparation of v-SWNTs using chemical assembly techniques, characterization, assembly kinetics, and electrochemical properties of v-SWNTs. We also review the applications of v-SWNTs in electrochemical and bioelectrochemical sensors, photoelectric conversion, and scanning probe microscopy. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.


Liu M.,CAS National Center for Nanoscience and Technology | Zheng Y.,Beihang University | Zhai J.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
Accounts of Chemical Research | Year: 2010

(Figure Presented) Super-antiwetting interfaces, such as superhydrophobic and superamphiphobic surfaces in air and superoleophobic interfaces in water, with special liquid-solid adhesion have recently attracted worldwide attention. Through tuning surface microstructures and compositions to achieve certain solid/liquid contact modes, we can effectively control the liquid-solid adhesion in a super-antiwetting state. In this Account, we review our recent progress in the design and fabrication of these bioinspired super-antiwetting interfaces with special liquid-solid adhesion. Low-adhesion superhydrophobic surfaces are biologically inspired, typically by the lotus leaf. Wettability investigated at microand nanoscale reveals that the low adhesion of the lotus surface originates from the composite contact mode, a microdroplet bridging several contacts, within the hierarchical structures. Recently high-adhesion superhydrophobic surfaces have also attracted research attention. These surfaces are inspired by the surfaces of gecko feet and rose petals. Accordingly, we propose two biomimetic approaches for the fabrication of high-adhesion superhydrophobic surfaces. First, to mimic a sticky gecko's foot, we designed structures with nanoscale pores that could trap air isolated from the atmosphere. In this case, the negative pressure induced by the volume change of sealed air as the droplet is pulled away from surface can produce a normal adhesive force. Second, we constructed microstructures with size and topography similar to that of a rose petal. The resulting materials hold air gaps in their nanoscale folds, controlling the superhydrophobicity in a Wenzel state on the microscale. Furthermore, we can tune the liquid-solid adhesion on the same superhydrophobic surface by dynamically controlling the orientations of microstructures without altering the surface composition. The superhydrophobic wings of the butterfly (Morpho aega) show directional adhesion: a droplet easily rolls off the surface of wings along one direction but is pinned tightly against rolling in the opposite direction. Through coordinating the stimuli-responsive materials and appropriate surface-geometry structures, we developed materials with reversible transitions between a low-adhesive rolling state and a high-adhesive pinning state for water droplets on the superhydrophobic surfaces, which were controlled by temperature and magnetic and electric fields. In addition to the experiments done in air, we also demonstrated bioinspired superoleophobic water/solid interfaces with special adhesion to underwater oil droplets and platelets. In these experiments, the high content of water trapped in the micro- and nanostructures played a key role in reducing the adhesion of the oil droplets and platelets. These findings will offer innovative insights into the design of novel antibioadhesion materials. © 2010 American Chemical society.


Liu C.,Beihang University | Ju J.,CAS Beijing National Laboratory for Molecular | Zheng Y.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
ACS Nano | Year: 2014

Inspired by novel creatures, researchers have developed varieties of fog drop transport systems and made significant contributions to the fields of heat transferring, water collecting, antifogging, and so on. Up to now, most of the efforts in directional fog drop transport have been focused on static surfaces. Considering it is not practical to keep surfaces still all the time in reality, conducting investigations on surfaces that can transport fog drops in both static and dynamic states has become more and more important. Here we report the wings of Morpho deidamia butterflies can directionally transport fog drops in both static and dynamic states. This directional drop transport ability results from the micro/nano ratchet-like structure of butterfly wings: the surface of butterfly wings is composed of overlapped scales, and the scales are covered with porous asymmetric ridges. Influenced by this special structure, fog drops on static wings are transported directionally as a result of the fog drops' asymmetric growth and coalescence. Fog drops on vibrating wings are propelled directionally due to the fog drops' asymmetric dewetting from the wings. © 2014 American Chemical Society.


Wu Y.,CAS Beijing National Laboratory for Molecular | Liu K.,Beihang University | Su B.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
Advanced Materials | Year: 2014

A superhydrophobic pillar-structured electrode leads to uncommon electrochemical behavior. The anti-wetting reaction surface restricts the contact between electrolyte and electrode to the pillar tops, as a result of trapped air pockets in the gaps between pillars. The electrochemical reaction occurs mainly at the solid/liquid/gas triphase interface, instead of the traditional solid/liquid diphase surface, yielding unique edge-growth structures - for example gold microflowers - on the top of each pillar. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wang Q.,Beihang University | Su B.,CAS Beijing National Laboratory for Molecular | Liu H.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2014

The controllable liquid transfer of a Chinese brush is attributable to the unique anisotropic multi-scale structures of the freshly emergent hairs. A large mass of liquid an be dynamically balanced within the brush as a cooperative effect of the Laplace pressure difference, the asymmetrical retention force, and gravity. Inspired by this, a device is developed with parallel hairs that allows for direct writing of micro-lines. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Bai H.,CAS National Center for Nanoscience and Technology | Wang L.,Beihang University | Ju J.,CAS Beijing National Laboratory for Molecular | Sun R.,Beihang University | And 3 more authors.
Advanced Materials | Year: 2014

Inspired by the water-collecting strategies of desert beetles and spider silk, a novel kind of surface with star-shaped wettablity patterns has been developed. By combining both wettability and shape gradients, the as-prepared surface has gained higher efficiency in water collection compared to circle-shaped wettability patterns and uniformly superhydrophilic or superhydrophobic surfaces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu C.-M.,CAS Beijing National Laboratory for Molecular | Xiong R.-G.,Nanjing Southeast University | Zhang D.-Q.,CAS Beijing National Laboratory for Molecular | Zhu D.-B.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2010

"Figure Presented" Both ferromagnetic and ferroelectric properties were observed in two enantiomerically pure nanoscale manganese cluster complexes supported by chiral Schiff base ligands, each of which comprises a 22-nucleus mixed-valence manganese(II/III) supratetrahedral cluster cation and an equilateral-triangle trinuclear manganese(III) cluster anion with C3 symmetry. Copyright © 2010 American Chemical Society.


Liu K.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Nano Today | Year: 2011

Multiscale structures of biological materials exhibit inherent multifunctional integration. This special biological solution provides some inspiration for scientists and engineers to design multifunctional artificial materials with multiscale structures. In this review, we focus on recent research progress in some typical biological materials (such as lotus leaves, rice leaves, butterfly wings, water strider legs, insect compound eyes, fish scales, red rose petals, brittlestars, spider silks, nacre, glass sponges, gecko feet, mussels, and others) and the corresponding bio-inspired multiscale materials possessing function integration. The challenges and perspectives for bio-inspired design of multifunctional structures in the future are also briefly addressed. © 2011 Elsevier Ltd. All rights reserved.


Bi H.,CAS Hefei Key Laboratory of Materials for Energy Conversion | Chen I.-W.,University of Pennsylvania | Lin T.,CAS Hefei Key Laboratory of Materials for Energy Conversion | Huang F.,CAS Hefei Key Laboratory of Materials for Energy Conversion | Huang F.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2015

3D architectures constructed from a tubular graphene network can withstand repeated >95% compression cycling without damage. Aided by intertubular covalent bonding, this material takes full advantage of the graphene tube's unique attributes, including complete pre- and post-buckling elasticity, outstanding electrical conductivity, and extraordinary physicochemical stability. A highly connected tubular graphene will thus be the ultimate, structurally robust, ultrastrong, ultralight material. © 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.


Zhang X.,Beihang University | Li Z.,Beihang University | Liu K.,Beihang University | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2013

Oil/water separation is a worldwide challenge. Learning from nature provides a promising approach for the construction of functional materials with oil/water separation. In this contribution, inspired by superhydrophobic self-cleaning lotus leaves and porous biomaterials, a facile method is proposed to fabricate polyurethane foam with simultaneous superhydrophobicity and superoleophilicity. Due to its low density, light weight, and superhydrophobicity, the as-prepared foam can float easily on water. Furthermore, the foam demonstrates super-repellency towards corrosive liquids, self-cleaning, and oil/water separation properties, possessing multifunction integration. We expect that this low-cost process can be readily and widely adopted for the design of multifunctional foams for large-area oil-spill cleanup. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhao X.,Tianjin Normal University | Zhang Y.,CAS Beijing National Laboratory for Molecular | Wang J.,CAS Beijing National Laboratory for Molecular
Chemical Communications | Year: 2012

Copper-catalyzed reaction of diazo compounds generates copper carbene intermediates that undergo diverse transformations. In recent years, the selectivity and efficiency of these important conversions have been further improved. In particular, breakthroughs have been made in catalytic asymmetric polar X-H bond insertion reactions. Moreover, novel transformations based on copper carbene, namely copper-catalyzed cross-couplings of diazo compounds, have emerged as powerful methods for carbon-carbon bond formations. This feature article summarizes the most recent developments in this area. © The Royal Society of Chemistry 2012.


Wang Q.,Beihang University | Yao X.,City University of Hong Kong | Liu H.,Beihang University | Quere D.,French National Center for Scientific Research | And 2 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2015

The ability to control drops and their movements on phobic surfaces is important in printing or patterning, microfluidic devices, and water-repellent materials. These materials are always micro-/nanotextured, and a natural limitation of repellency occurs when drops are small enough (as in a dew) to get trapped in the texture. This leads to sticky Wenzel states and destroys the superhydrophobicity of the material. Here, we show that droplets of volume ranging from femtoliter (fL) to microliter (μL) can be self-removed from the legs of water striders. These legs consist of arrays of inclined tapered setae decorated by quasi-helical nanogrooves. The different characteristics of this unique texture are successively exploited as water condenses, starting from self-penetration and sweeping effect along individual cones, to elastic expulsion between flexible setae, followed by removal at the anisotropic leg surface. We envision that this antifogging effect at a very small scale could inspire the design of novel applicable robust water-repellent materials for many practical applications.


Guo W.,CAS Beijing National Laboratory for Molecular | Cheng C.,Monash University | Wu Y.,Monash University | Jiang Y.,Beihang University | And 3 more authors.
Advanced Materials | Year: 2013

An electrogenetic layered graphene hydrogel membrane (GHM) possesses ultra-large interlayer spacing of about 10 nm, forming charged 2D nanocapillaries between graphene sheets that selectively permeate counter-ions and exclude co-ions. When an electrolyte flow goes through the GHM, it functions as an integrated 2D nanofluidic generator converting hydraulic motion into electricity. The maximum streaming conductance density approaches 16.8 μA cm-2 bar-1. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Dong Z.,CAS Beijing National Laboratory for Molecular | Ma J.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University
ACS Nano | Year: 2013

There is rapidly increasing research interest focused on manipulating and dispensing tiny droplets in nanotechnology and biotechnology. A micro/nanostructured superhydrophobic nozzle surface is one promising candidate for the realization of tiny droplet manipulating applications. Here, we explore the feasibility of using superhydrophobicity for guided dispensing of tiny water droplets. A facile dip-coating method is developed to prepare superhydrophobic needle nozzles (SNNs) based on commercial needle nozzles with reduced inner diameter. The SNNs can manipulate tiny droplets of different volumes by only changing the inner diameter of the nozzle, rather than reducing the nozzle size as a whole. Different from the previous electric-field-directed process or pyroelectrodynamic-driven technique, quasi-stable water drops down to the picoliter scale can be produced by SNNs without employing any extra driving mechanisms. Due to their intrinsic superhydrophobic nature, the SNNs also possess the properties of reducing sample liquid retention, improving sample volume transfer accuracy, and saving expensive reagents. In addition, this kind of dip-coating method can also be applied to micropipet tips, inkjet or bio-printer heads, etc. As the issues of reducing drop size and increasing drop volume accuracy are quite important in the laboratory and industry, this facile but effective superhydrophobic nozzle-coating method for manipulating tiny droplets could be of great help to make breakthroughs in next-generation liquid transport and biometric and inkjet printing devices. © 2013 American Chemical Society.


Tian D.,Beihang University | Song Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Chemical Society Reviews | Year: 2013

Patterning of controllable surface wettability has attracted wide scientific attention due to its importance in both fundamental research and practical applications. In particular, it is crucial to form clear image areas and non-image areas in printing techniques based on wetting and dewetting. This review summarizes the recent research on and applications of patterning of controllable surface wettability for printing techniques, with a focus on the design and fabrication of the precise surface wettability patterning by enhancing the contrast of hydrophilicity and hydrophobicity, such as superhydrophilicity and superhydrophobicity. The selected topics mainly include patterned surface wettability for lithographic printing with different plate-making techniques, patterned surface wettability for microcontact printing with a patterned wetting stamp and special wettability mediated patterning microtransfer printing, patterned surface wettability for inkjet printing with controllable surface wettability of the substrate and printing head to ink, and patterned surface wettability by a combination of different printing techniques. A personal perspective on the future development and remaining challenges of this research is also briefly discussed. © 2013 The Royal Society of Chemistry.


Chen Y.,CAS Beijing National Laboratory for Molecular | Li F.,Linköping University | Bo Z.,CAS Beijing National Laboratory for Molecular
Macromolecules | Year: 2010

We present an efficient and convenient synthesis of 3, 8- dibromophenanthridine derivatives and their conjugated polymers and demonstrate that phenanthridine-containing conjugated polymers can be used as luminescent chemosensor materials. High molecular weight poly(phenanthridine-co-fluorene)s (P1, P2) and poly(phenanthridine-co- p-phenylene) (P3) were synthesized by palladium-catalyzed SuzukiMiyaura-Schlüter polycondensation (SMSPC). These phenanthridine-containing polymers are of high quantum yields in solution and show reversible optical response to protonation and deprotonation of the phenanthridine rings. © 2010 American Chemical Society.


Xue B.,Beihang University | Gao L.,Beihang University | Hou Y.,Beihang University | Liu Z.,Agilent Technologies | And 2 more authors.
Advanced Materials | Year: 2013

A temperature controlled dual water/oil on-off switch is achieved by using a PMMA-b-PNIPAAm block-copolymer coated mesh, determined by the conformational change of the PNIPAAm chain around the lower critical solution temperature (LCST) and also the cooperation between PNIPAAm and PMMA. Water can permeate through the BCP-coated mesh, and oil cannot below the LCST, whereas oil can and water cannot above the LCST. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Ju J.,CAS Beijing National Laboratory for Molecular | Bai H.,CAS National Center for Nanoscience and Technology | Zheng Y.,Beihang University | Zhao T.,Beihang University | And 2 more authors.
Nature Communications | Year: 2012

Multiple biological structures have demonstrated fog collection abilities, such as beetle backs with bumps and spider silks with periodic spindle-knots and joints. Many Cactaceae species live in arid environments and are extremely drought-tolerant. Here we report that one of the survival systems of the cactus Opuntia microdasys lies in its efficient fog collection system. This unique system is composed of well-distributed clusters of conical spines and trichomes on the cactus stem; each spine contains three integrated parts that have different roles in the fog collection process according to their surface structural features. The gradient of the Laplace pressure, the gradient of the surface-free energy and multi-function integration endow the cactus with an efficient fog collection system. Investigations of the structure-function relationship in this system may help us to design novel materials and devices to collect water from fog with high efficiencies. © 2012 Macmillan Publishers Limited.


Lei T.,CAS Beijing National Laboratory for Molecular | Cao Y.,CAS Beijing National Laboratory for Molecular | Fan Y.,Xinjiang University | Liu C.-J.,Xinjiang University | And 2 more authors.
Journal of the American Chemical Society | Year: 2011

Two conjugated polymers, IIDDT and IIDT, based on an isoindigo core were developed for organic field-effect transisitors. Investigation of their field-effect performance indicated that IIDDT exhibited air-stable mobility up to 0.79 cm2 V-1 s-1, which is quite high among polymer FET materials. The facile preparation and high mobility of such polymers make isoindigo-based polymers very promising for application as solution-processable organic semiconductors for optoelectronic devices. © 2011 American Chemical Society.


Zhang F.,CAS Beijing National Laboratory for Molecular | Hu Y.,CAS Shanghai Institute of Organic Chemistry | Schuettfort T.,University of Cambridge | Di C.-A.,CAS Beijing National Laboratory for Molecular | And 7 more authors.
Journal of the American Chemical Society | Year: 2013

Substituted side chains are fundamental units in solution processable organic semiconductors in order to achieve a balance of close intermolecular stacking, high crystallinity, and good compatibility with different wet techniques. Based on four air-stable solution-processed naphthalene diimides fused with 2-(1,3-dithiol-2-ylidene)malononitrile groups (NDI-DTYM2) that bear branched alkyl chains with varied side-chain length and different branching position, we have carried out systematic studies on the relationship between film microstructure and charge transport in their organic thin-film transistors (OTFTs). In particular synchrotron measurements (grazing incidence X-ray diffraction and near-edge X-ray absorption fine structure) are combined with device optimization studies to probe the interplay between molecular structure, molecular packing, and OTFT mobility. It is found that the side-chain length has a moderate influence on thin-film microstructure but leads to only limited changes in OTFT performance. In contrast, the position of branching point results in subtle, yet critical changes in molecular packing and leads to dramatic differences in electron mobility ranging from ∼0.001 to >3.0 cm2 V-1 s-1. Incorporating a NDI-DTYM2 core with three-branched N-alkyl substituents of C11,6 results in a dense in-plane molecular packing with an unit cell area of 127 Å2, larger domain sizes of up to 1000 × 3000 nm2, and an electron mobility of up to 3.50 cm2 V-1 s-1, which is an unprecedented value for ambient stable n-channel solution-processed OTFTs reported to date. These results demonstrate that variation of the alkyl chain branching point is a powerful strategy for tuning of molecular packing to enable high charge transport mobilities. © 2013 American Chemical Society.


Ouyang F.,CAS Beijing National Laboratory for Molecular | Ouyang F.,University of South China | Peng S.,University of South China | Liu Z.,CAS Beijing National Laboratory for Molecular
ACS Nano | Year: 2011

The electronic structure of graphene antidot lattices (GALs) with zigzag hole edges was studied with first-principles calculations. It was revealed that half of the possible GAL patterns were unintentionally missed in the usual construction models used in earlier studies. With the complete models, the bandgap of the GALs was sensitive to the width W of the wall between the neighboring holes. A nonzero bandgap was opened in hexagonal GALs with even W, while the bandgap remained closed in those with odd W. Similar alternating gap opening/closing with W was also demonstrated in rhombohedral GALs. Moreover, analytical solutions of single-walled GALs were derived based on a tight-binding model to determine the location of the Dirac points and the energy dispersion, which confirmed the unique effect in GALs. © 2011 American Chemical Society.


Liu K.,Beihang University | Yao X.,CAS Beijing National Laboratory for Molecular | Jiang L.,Beihang University | Jiang L.,CAS Beijing National Laboratory for Molecular
Chemical Society Reviews | Year: 2010

Nature is a school for scientists and engineers. After four and a half billion years of stringent evolution, some creatures in nature exhibit fascinating surface wettability. Biomimetics, mimicking nature for engineering solutions, provides a model for the development of functional surfaces with special wettability. Recently, bio-inspired special wetting surfaces have attracted wide scientific attention for both fundamental research and practical applications, which has become an increasingly hot research topic. This Critical Review summarizes the recent work in bio-inspired special wettability, with a focus on lotus leaf inspired self-cleaning surfaces, plants and insects inspired anisotropic superhydrophobic surfaces, mosquito eyes inspired superhydrophobic antifogging coatings, insects inspired superhydrophobic antireflection coatings, rose petals and gecko feet inspired high adhesive superhydrophobic surfaces, bio-inspired water collecting surfaces, and superlyophobic surfaces, with particular focus on the last two years. The research prospects and directions of this rapidly developing field are also briefly addressed (159 references). © 2010 The Royal Society of Chemistry.


Mao N.,CAS National Center for Nanoscience and Technology | Mao N.,CAS Beijing National Laboratory for Molecular | Chen Y.,CAS National Center for Nanoscience and Technology | Liu D.,Tsinghua University | And 2 more authors.
Small | Year: 2013

The effect of surrounding solvents on the photoluminescence (PL) of MoS2 monolayers on Si/SiO2 substrates is studied. A redshift (up to -60 meV) is observed for MoS2 monolayers with nonhalogenated solvent surroundings. A blueshift (up to 60 meV) and intensity increase (2-50 times) are observed for monolayers with halogenated solvent surroundings. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gao X.,University of Science and Technology Beijing | Xu L.-P.,University of Science and Technology Beijing | Xue Z.,CAS Beijing National Laboratory for Molecular | Feng L.,Tsinghua University | And 4 more authors.
Advanced Materials | Year: 2014

Large-area dual-scaled porous nitrocellulose (p-NC) membranes are fabricated by a facile, inexpensive and scalable perforating approach. These p-NC membranes show stable superhydrophilicity in air and underwater superoleophobicity. The p-NC membranes with intrinsic nanopores and array of microscale perforated pores could selectively and efficiently separate water from various oil/water mixtures with high efficiency (> 99%) rapidly. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Teng M.,CAS Beijing National Laboratory for Molecular | Jia X.,CAS Beijing National Laboratory for Molecular | Chen X.,CAS Beijing National Laboratory for Molecular | Ma Z.,CAS Beijing National Laboratory for Molecular | Wei Y.,Tsinghua University
Chemical Communications | Year: 2011

We report herein the mechanochromic luminescent property of a dendritic polypeptide with a fluorescent aromatic moiety at the focal point. The different luminescent property of 1 under mechanical stimulus is attributed to the switch of self-assembled structures. Moreover, the photoluminescence property of 1 also depends on the thermal history. © 2011 The Royal Society of Chemistry.


Zhang H.,Tsinghua University | Zhang H.,CAS Beijing National Laboratory for Molecular | Yao B.,Tsinghua University | Yao B.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Journal of the American Chemical Society | Year: 2014

Copper and its salts are abundant, inexpensive, and eco-friendly and have been used as the surrogates of noble metals to effect arene C-H bond activation and transformations. Despite of the recent significant progress of the study, syntheses of high-valent arylcopper(II-III) compounds are still very rare and mechanisms of copper(II)-catalyzed reactions remain elusive. With the use of azacalix[1]arene[3]pyridines as a platform, a number of arylcopper(II) compounds were synthesized efficiently from the reaction of Cu(ClO4) 2 under ambient conditions. The resulting aryl-Cu(II) compounds, which contain an unprecedented (substituted) phenyl-Cu(II) s-bond, were stable under atmospheric conditions and can undergo facile oxidation reaction by free copper(II) ions or oxone to afford arylcopper(III) compounds in good yields. Both arylcopper(II) and arylcopper(III) compounds were characterized unambiguously by means of XRD, XPS, and NMR methods. Experimental evidence including reaction kinetics, LFER and KIE, and theoretical calculations indicated that the Cu(ClO4)2-mediated arene C-H bond activation proceeds plausibly through an electrophilic aromatic metalation pathway. The synthesis of high-valent arylcopper compounds and the reaction mechanism reported here highlight the diversity and richness of organocopper chemistry. © 2014 American Chemical Society.


Song J.-R.,CAS Beijing National Laboratory for Molecular | Sun J.,CAS Beijing National Laboratory for Molecular | Liu J.,Sun Yat Sen University | Huang Z.-T.,CAS Beijing National Laboratory for Molecular | Zheng Q.-Y.,CAS Beijing National Laboratory for Molecular
Chemical Communications | Year: 2014

Two new 2D COFs were synthesized from triformylcyclotrianisylene, which show not only thermal stability but also hydrolytic stability. CTV-COF-1 with smaller pore size stored a high hydrogen level of 1.3 wt% at low pressure, while CTV-COF-2 with larger pore size showed superior carbon dioxide uptake, up to 250 cm3 g-1 at 298 K and 50 bar. This journal is © The Royal Society of Chemistry.


Liu Q.,Tsinghua University | Liu Q.,CAS Beijing National Laboratory for Molecular
Electrochimica Acta | Year: 2014

Mg salts [Mg(NO3)2·6H2O]-doped TiO2 electrodes prepared well-optimized by the hydrothermal method. To prepare the working electrode, the TiO2 or Mg-doped TiO 2 slurry was coated onto the fluorine-doped tin oxide glass substrate by the doctor blade method and was then sintered at 450 °C. X-ray photoelectron spectroscopy (XPS) data indicated that the doped Mg ions exist in form of Mg2+, which can play a role as e- or h+ traps and reduce e-/h+ pair recombination rate, The Mott-Schottky plot indicates that the Mg-doped TiO2 photoanode shifts the flat band potential positively. The positive shift of the flat band potential improves the driving force of injected electrons from the LUMO of the dye to the conduction band of TiO2. This study show a photovoltaic efficiency of 7.12%, which is higher than that of the undoped TiO2 thin film (5.62%) and increase short-current by 26.7% from 14.9 mA to 19.1 mA. © 2014 Elsevier Ltd.


Shuai Z.,Tsinghua University | Geng H.,CAS Beijing National Laboratory for Molecular | Xu W.,CAS Beijing National Laboratory for Molecular | Liao Y.,Capital Normal University | Andre J.-M.,Tsinghua University
Chemical Society Reviews | Year: 2014

This review introduces the development and application of a multiscale approach to assess the charge mobility for organic semiconductors, which combines quantum chemistry, Kinetic Monte Carlo (KMC), and molecular dynamics (MD) simulations. This approach is especially applicable in describing a large class of organic semiconductors with intermolecular electronic coupling (V) much less than intramolecular charge reorganization energy (λ), a situation where the band description fails obviously. The charge transport is modeled as successive charge hopping from one molecule to another. We highlight the quantum nuclear tunneling effect in the charge transfer, beyond the semiclassical Marcus theory. Such an effect is essential for interpreting the "paradoxical" experimental finding that optical measurement indicated "local charge" while electrical measurement indicated "bandlike". Coupled MD and KMC simulations demonstrated that the dynamic disorder caused by intermolecular vibration has negligible effect on the carrier mobility. We further apply the approach for molecular design of n-type materials and for rationalization of experimental results. The charge reorganization energy is analyzed through decomposition into internal coordinates relaxation, so that chemical structure contributions to the intramolecular electron-phonon interaction are revealed and give helpful indication to reduce the charge reorganization energy. This journal is © the Partner Organisations 2014.


Lei C.-H.,CAS Beijing National Laboratory for Molecular | Wang D.-X.,CAS Beijing National Laboratory for Molecular | Zhao L.,Tsinghua University | Zhu J.,Ecole Polytechnique Federale de Lausanne | Wang M.-X.,Tsinghua University
Journal of the American Chemical Society | Year: 2013

A novel strategy for de novo synthesis of pyridines featuring an unprecedented α-addition of aldehyde and enamide to isonitrile as a key step is described. Under mild conditions, a cascade reaction involving Zn(OTf)2-promoted [1 + 5] cycloaddition of isonitrile with N-formylmethyl-substituted enamide, facile aerobic oxidative aromatization and intermolecular acyl transfer from the pyridinium nitrogen to the 5-hydroxy oxygen, and finally acylation of the 4-amino group by an external acyl chloride efficiently afforded 2-substituted 4-acylamino-5-acyloxypyridines in good to excellent yields. © 2013 American Chemical Society.


Shuai Z.,Tsinghua University | Peng Q.,CAS Beijing National Laboratory for Molecular
Physics Reports | Year: 2014

Photo- or electro-excited states in polyatomic molecules, aggregates, and conjugated polymers are at the center of organic light-emitting diodes (OLEDs). These can decay radiatively or non-radiatively, determining the luminescence quantum efficiency of molecular materials. According to Kasha's rule, light-emission is dictated by the lowest-lying excited state. For conjugated polymers, the electron correlation effect can lead the lowest-lying excited state to the even-parity 2Ag state which is non-emissive. To understand the nature of the low-lying excited state structure, we developed the density matrix renormalization group (DMRG) theory and its symmetrization scheme for quantum chemistry applied to calculate the excited states structure. We found there are three types of 1Bu/2Ag crossover behaviors: with electron correlation strength U, with bond length alternation, and with conjugation length. These directly influence the light-emitting property.For the electro-excitation, carriers (electron and hole) are injected independently, forming both singlet and triplet excited bound states with statistically 25% and 75% portions, respectively. We found that the exciton formation rate can depend on spin manifold, and for conjugated polymers, the singlet exciton can have larger formation rate leading to the internal electroluminescence quantum efficiency larger than the 25% spin statistical limit. It is originated from the interchain electron correlation as well as intrachain lattice relaxation.For the dipole allowed emissive state, the radiative decay process via either spontaneous emission or stimulated emission can be computed from electronic structure plus vibronic couplings. The challenging issue lies in the non-radiative decay via non-adiabatic coupling and/or spin-orbit coupling. We developed a unified correlation function formalism for the excited state radiative and non-radiative decay rates. We emphasized the low-frequency mode mixing (Duschinsky rotation) effect on the non-radiative decay. We further combined the non-adiabatic coupling and spin-orbit coupling for the triplet state decay (phosphorescence) quantum efficiency. All the formalisms have been developed analytically, which have been applied to optical spectroscopy, aggregation-induced emission phenomena, and polymer photovoltaic property. © 2013 Elsevier B.V.


Teng M.-J.,CAS Beijing National Laboratory for Molecular | Jia X.-R.,CAS Beijing National Laboratory for Molecular | Chen X.-F.,CAS Beijing National Laboratory for Molecular | Wei Y.,Tsinghua University
Angewandte Chemie - International Edition | Year: 2012

Color schemes: A mechanochromic material composed of two types of peptides bearing a pyrene group and rhodamine B moieties, respectively, displays multiluminescent colors, such as blue, green, and reddish in one sample (see picture). The mechanochromic behavior is based on a combined switching of molecular assemblies and chemical structure. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Tong S.,CAS Beijing National Laboratory for Molecular | Wang D.-X.,CAS Beijing National Laboratory for Molecular | Zhao L.,Tsinghua University | Zhu J.,Tsinghua University | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

Stable tertiary enamides and enecarbamates undergo highly enantioselective intramolecular nucleophilic addition to aldehyde units catalyzed by chiral binol-Ti complexes under mild conditions to produce the title compounds in up to 99.5% or greater enantiomeric excess. A positive nonlinear effect was detected and the formation of binol-Ti aggregates suggests an intricate asymmetric catalytic pathway. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhao Y.,CAS Beijing National Laboratory for Molecular | Ma W.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular | Ji H.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2012

The reaction pathways by which oxygen is incorporated into the substrate in the photocatalytic oxidation of terephthalic acid (TPTA) are vastly different on {001} and {101} facets of an anatase single crystal. This was established by controlling the percentage of {101} and {001} facets, isotopically tracing the origins of the hydroxy group, and studying dioxygen consumption and variance in the concentration of hydroxylation intermediate. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhou L.,CAS Beijing National Laboratory for Molecular | Zhou L.,Sun Yat Sen University | Ye F.,CAS Beijing National Laboratory for Molecular | Zhang Y.,CAS Beijing National Laboratory for Molecular | Wang J.,CAS Beijing National Laboratory for Molecular
Organic Letters | Year: 2012

Cyclopropylmethyl palladium species can be accessed by Pd-catalyzed reaction of either cyclopropyl N-tosylhydrazone with halide or N-tosylhydrazone with cyclopropyl halide. In both approaches migratory insertion of Pd carbene is the key process. These transformations constitute new approaches toward 1,3-butadiene derivatives. © 2012 American Chemical Society.


Duan H.,Tsinghua University | Wang D.,Tsinghua University | Kou Y.,CAS Beijing National Laboratory for Molecular | Li Y.,Tsinghua University
Chemical Communications | Year: 2013

Rhodium-nickel bimetallic nanocrystals were fabricated with high activity in hydrogenation of olefins, nitroarenes and arenes at room temperature, indicating that bimetallic nanocrystals of noble and non-noble metals represent a novel kind of nanocatalyst. This journal is © 2013 The Royal Society of Chemistry.


Wu S.-H.,CAS Beijing National Laboratory for Molecular | Abruna H.D.,Cornell University | Zhong Y.-W.,CAS Beijing National Laboratory for Molecular
Organometallics | Year: 2012

The reaction of 2,3-di(2-pyridyl)-5,6-diphenylpyrazine (dpdpz) with Re(CO) 5Cl in acetonitrile or toluene afforded mono-Re and bis-Re complexes [Re(CO) 3Cl-dpdpz] and [Re(CO) 3Cl-dpdpz-Re(CO) 3Cl], respectively. A heterodinuclear complex [Ru(bpy) 2-dpdpz-Re(CO) 3Cl](PF 6) 2 could be prepared by the reaction of [Re(CO) 3Cl-dpdpz] with Ru(bpy) 2Cl 2 or the reaction of Re(CO) 5Cl with a previously reported mono-Ru complex [Ru(bpy) 2-dpdpz](PF 6) 2 in moderate yields. Surprisingly, the reaction of [Re(CO) 3Cl-dpdpz] or [Re(CO) 3Cl-dpdpz-Re(CO) 3Cl] with Ru(tpy)Cl 3 in the presence of AgOTf both afforded an asymmetric bis-Ru complex [Ru(tpy)-dpdpz-RuCl(tpy)](PF 6) 2. The solid-state structures of [Re(CO) 3Cl-dpdpz-Re(CO) 3Cl] and [Ru(tpy)-dpdpz-RuCl(tpy)](PF 6) 2 were determined by single-crystal X-ray analysis. The electrochemical, absorption, and emission properties of these compounds were studied by cyclic voltammetric and spectroscopic analyses. In addition, DFT calculations were carried out to aid in the interpretation of these experimental findings. © 2012 American Chemical Society.


Wang X.-Y.,CAS Beijing National Laboratory for Molecular | Zhuang F.-D.,CAS Beijing National Laboratory for Molecular | Wang R.-B.,CAS Beijing National Laboratory for Molecular | Wang X.-C.,Xiamen University | And 3 more authors.
Journal of the American Chemical Society | Year: 2014

A straightforward strategy has been used to construct large BN-embedded π-systems simply from azaacenes. BN heterosuperbenzene derivatives, the largest BN heteroaromatics to date, have been synthesized in three steps. The molecules exhibit curved π-surfaces, showing two different conformations which are self-organized into a sandwich structure and further packed into a π-stacking column. The assembled microribbons exhibit good charge transport properties and photoconductivity, representing an important step toward the optoelectronic applications of BN-embedded aromatics. © 2014 American Chemical Society.


Teng M.-J.,CAS Beijing National Laboratory for Molecular | Jia X.-R.,CAS Beijing National Laboratory for Molecular | Yang S.,CAS Beijing National Laboratory for Molecular | Chen X.-F.,CAS Beijing National Laboratory for Molecular | Wei Y.,Tsinghua University
Advanced Materials | Year: 2012

A smart luminescent material whose emission color and emission intensity can be separately modulated by external force is demonstrated. The rational manipulation of rich noncovalent interactions and fluorophore packing style promotes an in-depth understanding between supramolecular structure and photophysical property and offers an effective strategy to modulate the light-emitting property in a predicative way. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhou Y.,CAS Beijing National Laboratory for Molecular | Zhou Y.,University of Chinese Academy of Sciences | Guo W.,CAS Beijing National Laboratory for Molecular | Cheng J.,Tsinghua University | And 3 more authors.
Advanced Materials | Year: 2012

Stimuli-responsive nanofluidic systems in room temperature ionic liquids (RTILs). The nanofluidic device can withstand high temperatures up to 200 °C, in which conventional water-based smart materials and nanodevices are invalid. The smart nanopores can be "irreversibly" turned off above the transition temperature of ca. 120-150 °C, actuated by the conformational change of the chemically-modified polymer brushes. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang H.,CAS Beijing National Laboratory for Molecular | Zhao L.,Tsinghua University | Wang D.-X.,CAS Beijing National Laboratory for Molecular | Wang M.-X.,Tsinghua University
Organic Letters | Year: 2013

Cu(OTf)2-catalyzed selective arene C-H bond hydroxylation and nitration reactions of azacalix[1]arene[3]pyridines were achieved using KNO 2 as an ambident O- and N-nucleophile under very mild aerobic conditions to yield functionalized azacalixaromatics. The reaction, which selectivity between hydroxylation and nitration was modulated by the reaction medium employed, proceeded through a Cu(II)-Cu(III)-Cu(I) mechanism. © 2013 American Chemical Society.


Xiao T.,Sun Yat Sen University | Dong X.,Sun Yat Sen University | Zhou L.,Sun Yat Sen University | Zhou L.,CAS Beijing National Laboratory for Molecular
Organic and Biomolecular Chemistry | Year: 2013

A general and practical method to synthesize 2-substituted benzofurans and indoles is described. This method employs easily accessible N-tosylhydrazones and o-hydroxy or o-amino phenylacetylenes as substrates. The reaction proceeds through a CuBr-catalyzed coupling-allenylation-cyclization sequence under ligand-free conditions. This journal is © 2013 The Royal Society of Chemistry.


Pan F.,CAS Beijing National Laboratory for Molecular | Lei Z.-Q.,CAS Beijing National Laboratory for Molecular | Lei Z.-Q.,CAS Chengdu Institute of Biology | Wang H.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2013

Marked absent: The pseudo-oxidative decarboxylative coupling of carboxylic acids and arenes using rhodium(I) in the absence of an oxidant is described. The study offers a new convenient method for the construction of C sp 2-C sp 2/C sp 3 bonds. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Gao Y.,CAS Beijing National Laboratory for Molecular | Gao Y.,CAS Dalian Institute of Chemical Physics | Hu G.,CAS Beijing National Laboratory for Molecular | Zhong J.,Soochow University of China | And 6 more authors.
Angewandte Chemie - International Edition | Year: 2013

Thanks to nitrogen introduced into the layered carbon framework of graphite, the chemical reactivity of the carbon atoms was increased. N-doped graphitic catalysts generate reactive oxygen species and display excellent activity for hydrocarbon activation even at room temperature. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu G.,CAS Beijing National Laboratory for Molecular | Zhang X.,Beijing Institute of Fashion Technology | Wang D.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2014

Poly(lactic acid) (PLA) is one of the most promising alternatives for petrochemical-based plastics. Crystallization mediation provides the simplest and most practical approach for enhancing the properties of PLA. Here, recent advances in understanding the relationship between crystalline structure and properties of PLA are summarized. Methods for manipulating crystallization towards high-performance PLA materials are introduced. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Kong H.,Tsinghua University | Liu D.,Tsinghua University | Liu D.,CAS Beijing National Laboratory for Molecular | Zhang S.,Tsinghua University | Zhang X.,Tsinghua University
Analytical Chemistry | Year: 2011

Cross-reactive sensor arrays, known as "chemical noses", offer an alternative to time-consuming analytical methods. Here, we report a sensor array based on nanomaterial-assisted chemiluminescence (CL) for protein sensing and cell discrimination. We have found that the CL efficiencies are improved to varied degrees for a given protein or cell line on catalytic nanomaterials. Distinct CL response patterns as "fingerprints" can be obtained on the array and then identified through linear discriminant analysis (LDA). The sensing of 12 kinds of proteins at three concentrations, as well as 12 types of human cell lines among normal, cancerous, and metastatic, has been performed. Compared with most fluorescent or colorimetric approaches which rely on the strong interaction between analytes and sensing elements, our array offers the advantage of both sensitivity and reversibility. © 2011 American Chemical Society.


Zhang X.,Tsinghua University | Wang S.,Tsinghua University | Liu M.,CAS Beijing National Laboratory for Molecular | Tao L.,Tsinghua University | Wei Y.,Tsinghua University
Nanoscale | Year: 2013

Water soluble and biocompatible fluorescent organic nanoparticles based on aggregation-induced emission (AIE) material were facilely prepared by mixing AIE material and surfactant. The utilization of such fluorescent organic nanoparticles for cell imaging applications was further explored. © 2013 The Royal Society of Chemistry.


Lei T.,CAS Beijing National Laboratory for Molecular | Dou J.-H.,CAS Beijing National Laboratory for Molecular | Cao X.-Y.,Xiamen University | Wang J.-Y.,CAS Beijing National Laboratory for Molecular | Pei J.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2013

Poly(p-phenylene vinylene) derivatives (PPVs) are one of the most widely investigated p-type polymers in organic electronics. PPVs generally exhibit electron mobilities lower than 10-4 cm2 V-1 s-1, thus hindering their applications in high-performance polymer field-effect transistors and organic photovoltaics. Herein, we design and synthesize a novel electron-deficient PPV derivative, benzodifurandione-based PPV (BDPPV). This new PPV derivative displays high electron mobilities up to 1.1 cm2 V-1 s-1 under ambient conditions (4 orders of magnitude higher than those of other PPVs), because it overcomes common defects in PPVs, such as conformational disorder, weak interchain interaction, and a high LUMO level. BDPPV represents the first polymer that can transport electrons over 1 cm2 V-1 s-1 under ambient conditions. © 2013 American Chemical Society.


Zhang X.,Tsinghua University | Wang S.,Tsinghua University | Liu M.,CAS Beijing National Laboratory for Molecular | Zhang Y.,Tsinghua University | And 2 more authors.
ACS Applied Materials and Interfaces | Year: 2013

Aggregation-induced emission (AIE) materials were facilely incorporated into mesoporous silica nanoparticles (MSNs) via one-pot surfactant templated method. Cell imaging and cancer therapy applications of such fluorescent MSNs were further explored. We demonstrated that AIE-MSN nanocomposites showed strong fluorescence and uniform morphology, making them promising for both cell imaging and cancer therapy. © 2013 American Chemical Society.


Ju J.,CAS Beijing National Laboratory for Molecular | Ju J.,University of Chinese Academy of Sciences | Xiao K.,CAS Beijing National Laboratory for Molecular | Xiao K.,University of Chinese Academy of Sciences | And 3 more authors.
Advanced Materials | Year: 2013

Inspired by the efficient fog collection on cactus spines, conical copper wires with gradient wettability are fabricated through gradient electrochemical corrosion and subsequent gradient chemical modification. These dual-gradient copper wires' fog-collection ability is demonstrated to be higher than that of conical copper wires with pure hydrophobic surfaces or pure hydrophilic surfaces, and the underlying mechanism is also analyzed. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Shi W.,CAS Beijing National Laboratory for Molecular | Xie X.-M.,Tsinghua University | Han C.C.,CAS Beijing National Laboratory for Molecular
Macromolecules | Year: 2012

The interplay between crystallization and phase separation has been intensively studied recently. In this study, we extended the research into a dynamically asymmetric blend composed of amorphous poly(methyl methacrylate) (PMMA) and crystalline poly(ethylene oxide) (PEO). The large dynamic asymmetry induces network stress in concentration growth. We find that crystallization is seriously frustrated when it couples with a simultaneous viscoelastic phase separation. In a single quench experiment, normal spherulites grew in a limited temperature range when crystallization was faster, while crystallization was frustrated at deep quenches when phase separation was faster. In a double quench experiment, crystallization was more difficult to occur after the prior phase separation at a higher temperature. The calorimetric results indicated that both melting temperatures and enthalpies of crystallization decreased in the coupled viscoelastic phase separation. We propose that it is the network stress in the concentration growth that leads to the frustration of crystallization. © 2012 American Chemical Society.


Chen P.,CAS Beijing National Laboratory for Molecular | Li C.,Tsinghua University | Liu D.,Tsinghua University | Li Z.,CAS Beijing National Laboratory for Molecular
Macromolecules | Year: 2012

A new type of DNA grafted polypeptide molecular brush was synthesized via a combination of ring-opening polymerization (ROP) and click chemistry. This conjugation method provides an easy and efficient approach to obtain a hybrid DNA-grafted polypeptide molecular bottlebrush. The structure and assembly behaviors of this hybrid brush were investigated using electrophoresis, UV-vis spectroscopy, transmission electron microscopy (TEM), and atomic force microscopy (AFM). Hierarchical supramolecular assemblies can be obtained through hybridization of two kinds of polypeptide-g-DNA molecular bottlebrushes containing complementary DNA side chains. We further demonstrated that such polypeptide-g-DNA can be hybridized with ds-DNA and DNA-grafted gold nanoparticles to form a supermolecular bottlebrush and hybrid bottlebrush, respectively. In addition, DNA-polypeptide hydrogel can be prepared by hybridization of polypeptide-g-DNA with a linker-ds-DNA, which contains the complementary "sticky ends" to serve as cross-linkers. © 2012 American Chemical Society.


Luo C.,CAS Beijing National Laboratory for Molecular | Zhao B.,University of Tennessee at Knoxville | Li Z.,CAS Beijing National Laboratory for Molecular
Polymer | Year: 2012

Four kinds of well defined poly(N-methacryloyl-L-amino acid)s were prepared via reversible addition fragmentation chain transfer polymerization. The effects of molecular structure, molecular weight, and end-group on their responsive properties in water were investigated. We found that the monomer structure is critical for the polymer to exhibit stimuli-responsive properties in water; only polymers derived from aspartic acid showed defined dual thermo- and pH-responsive properties. To study the effects of molecular weight and end group on the lower critical solution temperature behavior of poly(N-methacryloyl-L-β-isopropyl aspartic acid) (PMAIPAC), a series of PMAIPAC homopolymers with controlled molecular weights and narrow polydispersities were prepared and treated with excess radical initiators to give defined end groups. The cloud point of PMAIPAC was found to increase with the increase of solution pH, due to the ionization of carboxylic acid groups, and decrease with the increase of molecular weight. The structure of end groups also affects the cloud point of PMAIPAC particularly for low molecular weight samples at low pH. © 2012 Elsevier Ltd. All rights reserved.


Wang D.-X.,CAS Beijing National Laboratory for Molecular | Wang M.-X.,Tsinghua University
Journal of the American Chemical Society | Year: 2013

Anion-π interactions have been systematically studied using tetraoxacalix[2]arene[2]triazine 1, an electron-deficient and cavity self-tunable macrocyclic host, as an electron-neutral molecular probe. As revealed by electrospray ionization mass spectrometry (ESI-MS), fluorescence titration and X-ray crystallography, tetraoxacalix[2]arene[2]triazine has been found to form 1:1 complexes with four typical polyatomic anions of different geometries and shapes in the gaseous phase, in solution, and in the solid state. The association constants for the formation of anion-π complexes in acetonitrile are in the range of 239 to 16950 M-1, following the order of 1·NO3 - > 1·BF4 - > 1·PF6 - > 1·SCN -. X-ray molecular structures of the complexes showed that two opposing triazine rings of tetraoxacalix[2]arene[2]triazine act as a pair of tweezers to interact with the included anions through cooperative anion-π and lone-pair electron-π interactions. The generality of anion-π interactions and diverse anion-π interaction motifs can provide a new dimension in the study of molecular recognition and self-assembly. Moreover, this study potentiates the effect of anion-π interactions in chemical and biological systems, especially those involving anion and electron-deficient aromatic species. © 2012 American Chemical Society.


Chen Y.,CAS Beijing National Laboratory for Molecular | Wang D.-X.,CAS Beijing National Laboratory for Molecular | Huang Z.-T.,CAS Beijing National Laboratory for Molecular | Wang M.-X.,CAS Beijing National Laboratory for Molecular | Wang M.-X.,Tsinghua University
Chemical Communications | Year: 2011

A novel type of ditopic ion pair receptors based on anion-π interaction is reported. Oxacalix[2]arene[2]triazine azacrowns were synthesized efficiently from a one-pot reaction between 2,4-dichloro-4-methoxytriazine and 3,5-dihydroxybenzaldehyde followed by condensation with a diamine and reduction of bisimine; they acted as selective ditopic receptors to recognize ion pairs. © 2011 The Royal Society of Chemistry.


Wang M.-X.,Tsinghua University | Wang M.-X.,CAS Beijing National Laboratory for Molecular
Topics in Organometallic Chemistry | Year: 2011

Enantioselective biotransformations of nitriles using nitrile hydrolyzing microbial whole cell catalysts are a powerful method for the synthesis of highly enantioenriched carboxylic acids and amide derivatives. In this article, progress of Rhodococcus erythropolis AJ270-catalyzed enantioselective biotransformations of nitriles including various functionalized nitriles, α-and β-amino nitriles and β-hydroxy nitriles, cyclopropane-, oxirane-, aziridine-and azetidine-containing carbonitriles is summarized. Applications of enantioselective biotransformations of these nitriles in the synthesis of natural and bioactive products are also discussed. © 2011 Springer-Verlag Berlin Heidelberg.


Yang J.,University of California at Los Angeles | Zhu R.,University of California at Los Angeles | Hong Z.,University of California at Los Angeles | He Y.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Advanced Materials | Year: 2011

A robust inter-connecting layer for achieving high-performance tandem polymer solar cells is fabricated and demonstrated in polymer tandem solar cells with a PCE of 7.0%. This layer is optically transparent, electrically conductive, and physically strong. It is revealed that, under light illumination, charges are collected and recombined in the interlayer; under dark conditions, charges are generated and extracted from it. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liang Y.,CAS Beijing National Laboratory for Molecular | Liang Y.,Hunan Normal University | Zhang S.,CAS Beijing National Laboratory for Molecular | Xi Z.,CAS Beijing National Laboratory for Molecular | Xi Z.,CAS Shanghai Institute of Organic Chemistry
Journal of the American Chemical Society | Year: 2011

An efficient process involving Pd-catalyzed selective cleavage of a C(sp3)-Si bond and consequent intramolecular C(sp2)-Si coupling has been developed, affording benzosilolo[2,3-b]indoles as a new type of silicon-bridged polyheteroarene in excellent yields. Aldehyde was found for the first time to be able to promote the efficiency of the catalytic process remarkably. © 2011 American Chemical Society.


Ding S.-Y.,Lanzhou University | Gao J.,Lanzhou University | Wang Q.,Lanzhou University | Wang Q.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Journal of the American Chemical Society | Year: 2011

Covalent organic frameworks (COFs) are crystalline porous solids with well-defined two- or three-dimensional molecular structures. Although the structural regularity provides this new type of porous material with high potentials in catalysis, no example has been presented so far. Herein, we report the first application of a new COF material, COF-LZU1, for highly efficient catalysis. The easily prepared imine-linked COF-LZU1 possesses a two-dimensional eclipsed layered-sheet structure, making its incorporation with metal ions feasible. Via a simple post-treatment, a Pd(II)-containing COF, Pd/COF-LZU1, was accordingly synthesized, which showed excellent catalytic activity in catalyzing the Suzuki-Miyaura coupling reaction. The superior utility of Pd/COF-LZU1 in catalysis was elucidated by the broad scope of the reactants and the excellent yields (96-98%) of the reaction products, together with the high stability and easy recyclability of the catalyst. We expect that our approach will further boost research on designing and employing functional COF materials for catalysis. © 2011 American Chemical Society.


Zhang X.,Hunan Normal University | Zeng W.,Hunan Normal University | Yang Y.,Hunan Normal University | Huang H.,Hunan Normal University | And 2 more authors.
Organic Letters | Year: 2014

A new, highly efficient procedure for the synthesis of benzothiazoles from easily available N-benzyl-2-iodoaniline and potassium sulfide has been developed. The results show copper-catalyzed double C-S bond formation via a traditional cross-coupling reaction and an oxidative cross-coupling reaction. © 2014 American Chemical Society.


Yao C.-J.,CAS Beijing National Laboratory for Molecular | Zhong Y.-W.,CAS Beijing National Laboratory for Molecular | Nie H.-J.,CAS Beijing National Laboratory for Molecular | Abrun H.D.,Cornell University | Yao J.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2011

Reductive electropolymerization of the biscyclometalated ruthenium complex [(vtpy)Ru(tpb)Ru(vtpy)] 2+ [vtpy = 4′-vinyl-2,2′:6′, 2″-terpyridine; tpb = 1,2,4,5-tetra(2-pyridyl)benzene] proceeded smoothly on electrode surfaces. Thanks to the strong electron coupling between the ruthenium centers of the individual monomeric units and strong intervalence charge-transfer absorption in the mixed valence state, the produced adherent metallopolymeric films exhibited near-IR electrochromism with tricolor switching, good contrast ratio (40% at 1165 nm), short response time, low-switching voltage, and long memory time. © 2011 American Chemical Society.


Zhang C.,CAS Beijing National Laboratory for Molecular | Fu L.,CAS Beijing National Laboratory for Molecular | Liu N.,CAS Beijing National Laboratory for Molecular | Liu M.,Tsinghua University | And 2 more authors.
Advanced Materials | Year: 2011

A facile strategy to grow nitrogen-doped graphene using embedded nitrogen and carbon in metal substrate via a segregation method is reported. As doping is concurrently carried out in the segregation process of the carbon species, N atoms can be substitutionally doped into the graphene lattice. This approach allows precise control of the doping degree and location, which enables growing various heterojunctions at the desired location. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Sekine J.,RIKEN | Luo S.-C.,RIKEN | Wang S.,CAS Beijing National Laboratory for Molecular | Zhu B.,RIKEN | And 2 more authors.
Advanced Materials | Year: 2011

Nanostructured conducting polymer nanodots are prepared by electropolymerization of carboxylic acid group functionalized monomer in dichloromethane directly onto substrates. They demonstrate enhanced yields for the capture of tumor cells compared to smooth surfaces due to a synergistic effect of the capture agents and nanostructures. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang X.,Tsinghua University | Liu M.,CAS Beijing National Laboratory for Molecular | Yang B.,Tsinghua University | Wei Y.,Tsinghua University
Colloids and Surfaces B: Biointerfaces | Year: 2013

Tetraphenylethene-based (TPE) aggregation-induced emission fluorescent organic nanoparticles (FONs) were facilely prepared via Schiff base condensation with e{open}-polylysine (Ply) and subsequent reduction to form stable C. N covalent bond. Thus obtained TPE-Ply FONs were characterized by a series of techniques including fluorescent spectroscopy, Fourier transform infrared spectroscopy and transmission electron microscopy. Biocompatibility evaluation and cell uptake behavior of TPE-Ply FONs were further investigated to explore their potential biomedical application. We demonstrated that such FONs showed high water dispersibility, intense fluorescence, uniform morphology (100-200. nm) and excellent biocompatibility, making them promising for cell imaging application. © 2013 Elsevier B.V.


He L.,CAS Beijing National Laboratory for Molecular | Zhao L.,Tsinghua University | Wang D.-X.,CAS Beijing National Laboratory for Molecular | Wang M.-X.,Tsinghua University
Organic Letters | Year: 2014

Catalyzed by a chiral BINOL-Ti(OiPr)4 complex, various stable tertiary enamides reacted with salicylaldehydes to afford diverse cis,trans-configured 4-chromanols that contain three continuous stereogenic centers in good yields with excellent diastereoselectivity and enantioselectivity. The reaction proceeded through the addition of enamide to aldehyde followed by the intramolecular interception of the resulting iminium by the hydroxy group. Oxidation of the resulting 4-chromanols yielded almost quantitatively chroman-4-one derivatives which underwent diastereospecific reduction with NaBH4 to produce cis,cis-configured 4-chromanols. © 2014 American Chemical Society.


Fan X.,CAS Beijing National Laboratory for Molecular | Cui C.,CAS Beijing National Laboratory for Molecular | Fang G.,Wuhan University | Wang J.,Hubei University | And 4 more authors.
Advanced Functional Materials | Year: 2012

Polymer solar cells (PSCs) with poly(3-hexylthiophene) (P3HT) as a donor, an indene-C 70 bisadduct (IC 70BA) as an acceptor, a layer of indium tin oxide modified by MoO 3 as a positive electrode, and Ca/Al as a negative electrode are presented. The photovoltaic performance of the PSCs was optimized by controlling spin-coating time (solvent annealing time) and thermal annealing, and the effect of the spin-coating times on absorption spectra, X-ray diffraction patterns, and transmission electron microscopy images of P3HT/IC 70BA blend films were systematically investigated. Optimized PSCs were obtained from P3HT/IC 70BA (1:1, w/w), which exhibited a high power conversion efficiency of 6.68%. The excellent performance of the PSCs is attributed to the higher crystallinity of P3HT and better a donor-acceptor interpenetrating network of the active layer prepared under the optimized conditions. In addition, PSCs with a poly(3,4-ethylenedioxy-thiophene) :poly(styrenesulfonate) (PEDOT:PSS) buffer layer under the same optimized conditions showed a PCE of 6.20%. The results indicate that the MoO 3 buffer layer in the PSCs based on P3HT/IC 70BA is superior to that of the PEDOT:PSS buffer layer, not only showing a higher device stability but also resulting in a better photovoltaic performance of the PSCs. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lin X.,Harbin Institute of Technology | He Q.,Harbin Institute of Technology | Li J.,CAS Beijing National Laboratory for Molecular
Chemical Society Reviews | Year: 2012

Confined surface gradients consisting of polymer brushes have great potential in various applications such as microfluidic devices, sensors, and biophysical research. Among the available fabrication approaches, nanolithographies combined with self-assembled monolayers and surface-initiated polymerization have became powerful tools to engineer confined gradients or predefined complex gradients on the nanometre size. In this tutorial review, we mainly highlight the research progress of the fabrication of confined polymer brush gradients by using electron beam, laser, and probe-based nanolithographies and the physical base for these approaches. The application of these polymer brush gradients in biomedical research is also addressed. © The Royal Society of Chemistry 2012.


Wu L.,CAS Beijing National Laboratory for Molecular | Wu L.,Harbin Institute of Technology | He Y.-M.,CAS Beijing National Laboratory for Molecular | Fan Q.-H.,CAS Beijing National Laboratory for Molecular
Advanced Synthesis and Catalysis | Year: 2011

A new catalyst separation and recycling protocol combining magnetic nanoparticles and host-guest assembly was developed. The catalyst, (η6-arene)[N-(para-toluenesulfonyl)-1,2-diphenylethylenediamine] ruthenium trifluoromethanesulfonate [Ru(OTf)(TsDPEN)(η6-arene)] bearing a dialkylammonium salt tag, was easily separated from the reaction mixtures by magnet-assisted decantation, on basis of the formation of a pseudorotaxane complex by using dibenzo[24]crown-8-modified Fe3O 4 nanoparticles. The ruthenium catalyst has been successfully reused at least 5 times with the retention of enantioselectivity but at the expense of relatively low catalytic activities in the asymmetric hydrogenation of 2-methylquinoline. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Fang X.,CAS Beijing National Laboratory for Molecular | Tan W.,University of Florida | Tan W.,Hunan University
Accounts of Chemical Research | Year: 2010

Molecular medicine is an emerging field focused on understanding the molecular basis of diseases and translating this information into strategies for diagnosis and therapy. This approach could lead to personalized medical treatments. Currently, our ability to understand human diseases at the molecular level is limited by the lack of molecular tools to identify and characterize the distinct molecular features of the disease state, especially for diseases such as cancer. Among the new tools being developed by researchers including chemists, engineers, and other scientists is a new class of nucleic acid probes called aptamers, which are ssDNA/RNA molecules selected to target a wide range of molecules and even cells. In this Account, we will focus on the use of aptamers, generated from cell-based selections, as a novel molecular tool for cancer research. Cancers originate from mutations of human genes. These genetic alterations result in molecular changes to diseased cells, which, in turn, lead to changes in cell morphology and physiology. For decades, clinicians have diagnosed cancers primarily based on the morphology of tumor cells or tissues. However, this method does not always give an accurate diagnosis and does not allow clinicians to effectively assess the complex molecular alterations that are predictive of cancer progression. As genomics and proteomics do not yet allow a full access to this molecular knowledge, aptamer probes represent one effective and practical avenue toward this goal. One special feature of aptamers is that we can isolate them by selection against cancer cells without prior knowledge of the number and arrangement of proteins on the cellular surface. These probes can identify molecular differences between normal and tumor cells and can discriminate among tumor cells of different classifications, at different disease stages, or from different patients. This Account summarizes our recent efforts to develop aptamers through cell-SELEX for the study of cancer and apply those aptamers in cancer diagnosis and therapy. We first discuss how we select aptamers against live cancer cells. We then describe uses of these aptamers. Aptamers can serve as agents for molecular profiling of spedfic cancer types. They can also be used to modify therapeutic reagents to develop targeted cancer therapies. Aptamers are also aiding the discovery of new cancer biomarkers through the recognition of membrane protdn targets. Importantly, we demonstrate how molecular assemblies can integrate the properties of aptamers and, for example, nanoparticles or microfluidic devices, to improve cancer cell enrichment, detection and therapy. Figure Presented. © 2010 American Chemical Society.


Lei T.,CAS Beijing National Laboratory for Molecular | Xia X.,Xinjiang University | Wang J.-Y.,CAS Beijing National Laboratory for Molecular | Liu C.-J.,Xinjiang University | Pei J.,CAS Beijing National Laboratory for Molecular
Journal of the American Chemical Society | Year: 2014

The charge carrier mobility of p-type and ambipolar polymer field-effect transistors (FETs) has been improved substantially. Nonetheless, high-mobility n-type polymers are rare, and few can be operated under ambient conditions. This situation is mainly caused by the scarcity of strong electron-deficient building blocks. Herein, we present two novel electron-deficient building blocks, FBDOPV-1 and FBDOPV-2, with low LUMO levels down to -4.38 eV. On the basis of both building blocks, we develop two poly(p-phenylene vinylene) derivatives (PPVs), FBDPPV-1 and FBDPPV-2, for high-performance n-type polymer FETs. The introduction of the fluorine atoms effectively lowers the LUMO levels of both polymers, leading to LUMO levels as low as -4.30 eV. Fluorination endows both polymers with not only lower LUMO levels, but also more ordered thin-film packing, smaller π-π stacking distance, stronger interchain interaction and locked conformation of polymer backbones. All these factors provide FBDPPV-1 with high electron mobilities up to 1.70 cm2 V-1 s -1 and good stability under ambient conditions. Furthermore, when polymers have different fluorination positions, their backbone conformations in solid state differ, eventually leading to different device performance. © 2014 American Chemical Society.


Zhai T.,Japan International Center for Materials Nanoarchitectonics | Zhai T.,CAS Beijing National Laboratory for Molecular | Li L.,Japan International Center for Materials Nanoarchitectonics | Ma Y.,CAS Beijing National Laboratory for Molecular | And 7 more authors.
Chemical Society Reviews | Year: 2011

One-dimensional inorganic nanostructures have drawn prime attention due to their potential for understanding fundamental physical concepts and constructing nanoscale electronic and optoelectronic devices. This critical review mainly focuses on our recent research progresses in 1D inorganic nanostructures, including their rational synthesis and potential applications, with an emphasis on field-emitter and photodetector applications. Firstly, we will discuss the rational design of synthetic strategies and the synthesis of 1D nanostructures via a vapour phase approach. Secondly, we will present our recent progresses with respect to several kinds of important inorganic nanostructures and their field-emission and photoconductivity characteristics. Finally, we conclude this review with some perspectives/outlook and future research in these fields (212 references). © 2011 The Royal Society of Chemistry.


Lei T.,CAS Beijing National Laboratory for Molecular | Dou J.-H.,CAS Beijing National Laboratory for Molecular | Ma Z.-J.,Xinjiang University | Yao C.-H.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Journal of the American Chemical Society | Year: 2012

Ambipolar transport behavior in isoindigo-based conjugated polymers is observed for the first time. Fluorination on the isoindigo unit effectively lowers the LUMO level of the polymer and significantly increases the electron mobility from 10-2 to 0.43 cm2 V-1 s -1 while maintaining high hole mobility up to 1.85 cm2 V-1 s-1 for FET devices fabricated in ambient. Further investigation indicates that fluorination also affects the interchain interactions of polymer backbones, thus leading to different polymer packing in thin films. © 2012 American Chemical Society.


He M.,Sinopec | He M.,East China Normal University | Sun Y.,CAS Shanghai Advanced Research Institute | Sun Y.,Shanxi Institute of Coal CAS Chemistry | Han B.,CAS Beijing National Laboratory for Molecular
Angewandte Chemie - International Edition | Year: 2013

How green was my valley: Green carbon science focuses on the transformations of carbon-containing compounds in the entire carbon cycle. The ultimate aim is to use carbon resources efficiently and minimize the net CO 2 emission. This holistic view also has ramifications for related fields including petroleum refining and the production of liquid fuels and chemicals from coal, methane, CO2, and biomass. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Duan L.,Northwest Institute of Nuclear Technology | Yan X.,Max Planck Institute of Colloids and Interfaces | Wang A.,CAS Beijing National Laboratory for Molecular | Jia Y.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular
ACS Nano | Year: 2012

Seeking safe and effective artificial blood substitutes based on hemoglobin (Hb) as oxygen carriers is an important topic. A significant challenge is to enhance the loading content of Hb in a well-defined structure. Here we report a facile and controllable avenue to fabricate Hb spheres with a high loading content by templating decomposable porous CaCO 3 particles in collaboration with covalent layer-by-layer assembly technique. The surface of the Hb spheres was further chemically modified by biocompatible polyethylene glycol to protect and stabilize the system. Multiple characterization techniques were employed to reveal the loading and density of Hb in an individual CaCO 3 particle. The results demonstrate that the strategy developed in this work is effective and flexible for construction of the highly loaded Hb spheres. More importantly, such Hb spheres retain their carrying-releasing oxygen function. It may thus have great potential to develop Hb spheres with highly loaded content as realistic artificial blood substitutes in the future. © 2012 American Chemical Society.


Duan R.,Huazhong University of Science and Technology | Zuo X.,CAS Shanghai Institute of Applied Physics | Wang S.,CAS Beijing National Laboratory for Molecular | Quan X.,No 1 Hospital | And 5 more authors.
Journal of the American Chemical Society | Year: 2013

Through rational design of a functional molecular probe with high sequence specificity that takes advantage of sensitive isothermal amplification with simple operation, we developed a one-pot hairpin-mediated quadratic enzymatic amplification strategy for microRNA (miRNA) detection. Our method exhibits ultrahigh sensitivity toward miR-21 with detection limits of 10 fM at 37 C and 1 aM at 4 C, which corresponds to nine strands of miR-21 in a 15 μL sample, and it is capable of distinguishing among miRNA family members. More importantly, the proposed approach is also sensitive and selective when applied to crude extractions from MCF-7 and PC3 cell lines and even patient tissues from intraductal carcinoma and invasive ductal carcinoma of the breast. © 2013 American Chemical Society.


Wang L.,CAS Beijing National Laboratory for Molecular | Wang L.,Harbin Institute of Technology | Wu B.,CAS Beijing National Laboratory for Molecular | Chen J.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Advanced Materials | Year: 2014

Viable and general techniques that allow effective size control of triangular-shaped, single-crystal, monolayer h-BN domains grown by the CVD method, direct optical visualization of h-BN domains, and the cleaning of the h-BN surface to achieve reliable graphene device quality are reported for the first time. This study points to a critical role of the interfacial properties between the graphene and the monolayer h-BN in determining reliable, enhanced graphene-device performance. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Lei T.,CAS Beijing National Laboratory for Molecular | Dou J.-H.,CAS Beijing National Laboratory for Molecular | Ma Z.-J.,Xinjiang University | Liu C.-J.,Xinjiang University | And 2 more authors.
Chemical Science | Year: 2013

For the first time, ambient-stable and balanced carrier transport is achieved in polymer ambipolar field-effect transistors (FETs) and inverters with high performance. With chlorinated isoindigo polymers, FETs fabricated in ambient conditions show hole mobilities up to 0.81 cm2 V-1 s-1 and dramatically increased electron mobilities from 10 -2 to 0.66 cm2 V-1 s-1. Hence, chlorination is effective to modulate electronic properties and improve the device performance of conjugated polymers. © 2013 The Royal Society of Chemistry.


Yin Z.,CAS Dalian Institute of Chemical Physics | Zhou W.,Lehigh University | Gao Y.,CAS Beijing National Laboratory for Molecular | Ma D.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Chemistry - A European Journal | Year: 2012

Monodisperse bimetallic Pd-Cu nanoparticles with controllable size and composition were synthesized by a one-step multiphase ethylene glycol (EG) method. Adjusting the stoichiometric ratio of the Pd and Cu precursors afforded nanoparticles with different compositions, such as Pd 85-Cu 15, Pd 56-Cu 44, and Pd 39-Cu 61. The nanoparticles were separated from the solution mixture by extraction with non-polar solvents, such as n-hexane. Monodisperse bimetallic Pd-Cu nanoparticles with narrow size-distribution were obtained without the need for a size-selection process. Capping ligands that were bound to the surface of the particles were removed through heat treatment when the as-prepared nanoparticles were loaded onto a Vulcan XC-72 carbon support. Supported bimetallic Pd-Cu nanoparticles showed enhanced electrocatalytic activity towards methanol oxidation compared with supported Pd nanoparticles that were fabricated according to the same EG method. For a bimetallic Pd-Cu catalyst that contained 15% Cu, the activity was even comparable to the state-of-the-art commercially available Pt/C catalysts. A STEM-HAADF study indicated that the formation of random solid-solution alloy structures in the bimetallic Pd 85-Cu 15/C catalysts played a key role in improving the electrochemical activity. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang Z.,CAS Beijing National Laboratory for Molecular | Zhang Z.,China National Institute of Biological Sciences | Zhang Y.,CAS Beijing National Laboratory for Molecular | Wang J.,CAS Beijing National Laboratory for Molecular
ACS Catalysis | Year: 2011

Carbonylation of metal carbene complexes, including the carbonylation of Group VI Fischer carbenes, is reviewed in this article. In particular, transition metal-catalyzed carbonylation of metal carbene complexes with carbon monoxide is discussed in detail. This type of carbonylation reactions provides an efficient access to ketene species, which are highly important in organic synthesis. © 2011 American Chemical Society.


Liu C.,CAS Beijing National Laboratory for Molecular | Jin Q.,CAS Beijing National Laboratory for Molecular | Jin Q.,Zhengzhou University of Light Industry | Lv K.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Chemical Communications | Year: 2014

Water was found to tune the self-assembled nanostructures of a cationic amphiphile in organic solvents from nanofibers to helical tapes, helical tubes and chiral nanotwists with various pitch lengths depending on water content. Inversion of CD spectra was observed in the water-triggered polar and non-polar solvent gels. This journal is © the Partner Organisations 2014.


Miao W.,Lingnan Normal University | Yang D.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular
Chemistry - A European Journal | Year: 2015

Abstract A new class of homologous gelators, LG12-(CH2)n-BSA, composed of bipyridinyl groups, L-glutamic moieties having double dodecyl chains, and linked alkyl spacers with different lengths were synthesized. It was found that these gelators could immobilize medium-polarity solvents readily and the behaviors of these gels showed a dependence on the spacer length. Of all the gels, the LG12-(CH2)11-BSA gels exhibited self-healing property and multiple-stimulus responsibility, such as heating, shaking, and sonication. The investigation of CD spectra indicated that the supramolecular chirality, which was attributed to the chiral transfer from the chiral center to the assemblies, was also closely related to the length of methylene spacers. The longer the alkyl spacers, the weaker the transmitted supramolecular chirality. Only LG12-(CH2)1-BSA gelators, which had the shortest spacers, formed right-handed nanoscale chiral twists owing to crowded hydrogen bonding interactions. Moreover, the high-polarity solvent DMF was found to be able to regulate the chiral twist as well as its pitch length readily. A new twist on healing: Self-healing supramolecular gels that are responsive to multiple stimuli were developed. The formation of nanoscale twists could be controlled by the length of the methylene spacers of the gelator molecules. The pitch of these twists could be regulated by DMF. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cui C.,CAS Beijing National Laboratory for Molecular | Cui C.,Hong Kong Baptist University | Wong W.-Y.,Hong Kong Baptist University | Wong W.-Y.,Shenzhen University | And 2 more authors.
Energy and Environmental Science | Year: 2014

Low bandgap and two-dimensional (2D)-conjugated copolymers based on benzo[1,2-b:4,5-b′]dithiophene with conjugated thiophene side chains (BDTT) and thieno[3,4-b]thiophene with electron-withdrawing substituents (TT) are attractive high efficiency polymer donor materials in polymer solar cells (PSCs). In this work, we introduced an alkylthio substituent on the thiophene side chain in the polymer and synthesized a new low bandgap 2D-conjugated polymer PBDTT-S-TT. The alkylthio substituent increased the hole mobility of the polymer to 4.08 × 10-3 cm2 V-1 s -1 and down-shifted the HOMO energy level of the polymer by 0.11 eV with absorption of the polymer film red-shifted slightly. The PSCs based on PBDTT-S-TT as a donor and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM) as an acceptor without solvent additive treatment demonstrated a high open-circuit voltage (Voc) of 0.84 V, leading to a high power conversion efficiency (PCE) of 8.42%, under the illumination of AM 1.5 G 100 mW cm-2. For comparison, the Voc and PCE of the devices based on the corresponding parent polymer PBDTT-TT with the device optimization of 3% DIO additive treatment are 0.77 V and 7.38%, respectively. The enhanced Voc value of 0.84 V for the PSC based on PBDTT-S-TT should be benefited from the down-shifted HOMO energy level of the polymer. The results indicate that the alkylthio substitution is an effective way to further improve the photovoltaic performance of the 2D-conjugated polymer donor materials in PSCs. © The Royal Society of Chemistry 2014.


Ferrand Y.,French National Center for Scientific Research | Gan Q.,French National Center for Scientific Research | Gan Q.,CAS Beijing National Laboratory for Molecular | Kauffmann B.,French National Center for Scientific Research | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2011

Screwed in place: An anti-parallel double-helical aromatic oligoamide foldamer was shown to bind to a series of rodlike guests of various lengths upon the winding of the duplex around the guests (see scheme). Solid-state crystal structures of the host-guest complexes show that the two strands of the duplex undergo a relative screw motion to adjust the distance between hydrogen-bond donors located at the end of one of their extremities so that they bind to hydrogen-bond acceptors of the guest. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Jin Q.,CAS Beijing National Laboratory for Molecular | Jin Q.,Zhengzhou University of Light Industry | Zhang L.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular
Chemistry - A European Journal | Year: 2013

The self-assembly of a low-molecular-weight organogelator into various hierarchical structures has been achieved for a pyridylpyrazole linked L-glutamide amphiphile in different solvents. Upon gel formation, supramolecular chirality was observed, which exhibited an obvious dependence on the polarity of the solvent. Positive supramolecular chirality was obtained in nonpolar solvents, whereas it was inverted into negative supramolecular chirality in polar solvents. Moreover, the gelator molecules self-assembled into a diverse array of nanostructures over a wide scale range, from nanofibers to nanotubes and microtubes, depending on the solvent polarity. Such morphological changes could even occur for the xerogels in the solvent vapors. We found that the interactions between the pyridylpyrazole headgroups and the solvents could subtly change the stacking of the molecules and, hence, their self-assembled nanostructures. This work exemplifies that organic solvents can significantly involve the gelation, as well as tune the structure and properties, of a gel. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Usharani D.,Hebrew University of Jerusalem | Lai W.,Renmin University of China | Li C.,CAS Fujian Institute of Research on the Structure of Matter | Li C.,Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry | And 3 more authors.
Chemical Society Reviews | Year: 2014

This is a tutorial on the usage of valence bond (VB) diagrams for understanding chemical reactivity in general, and hydrogen atom transfer (HAT) reactivity in particular. The tutorial instructs the reader how to construct the VB diagrams and how to estimate HAT barriers from raw data, starting with the simplest reaction H + H2 and going all the way to HAT in the enzyme cytochrome P450. Other reactions are treated as well, and some unifying principles are outlined. The tutorial projects the unity of reactivity treatments, following Coulson's dictum "give me insight, not numbers", albeit with its modern twist: giving numbers and insight. This journal is © the Partner Organisations 2014.


Yin Z.,Tianjin Polytechnic University | Lin L.,CAS Beijing National Laboratory for Molecular | Ma D.,CAS Beijing National Laboratory for Molecular
Catalysis Science and Technology | Year: 2014

Nanostructured Pd-based electrocatalysts have a large impact on cost, performance, and durability in the development of fuel cells. This review article provides an overview of recent advances in Pd-based electrocatalysts with a well-defined structure that can be applied for alcohol oxidation and oxygen reduction in an alkaline medium in direct alcohol fuel cells. These Pd-based catalytic materials include Pd electrocatalysts with different morphologies, monodisperse bimetallic Pd-based nanoparticles with different compositions and Pd-based nanoparticles with a well-controlled shape. Emphasis is placed on the atomic-level design of the nanoparticles' structure, and the origin of their electrochemical activity. The ways to enhance the electrocatalytic performance and design principles for Pd-based catalysts are discussed. This will help to shed light on the future development of non-Pt catalysts for fuel cells and accelerate the commercialization of fuel cell technology. © 2014 the Partner Organisations.


Kang R.,CAS Beijing National Laboratory for Molecular | Kang R.,University of Chinese Academy of Sciences | Chen H.,CAS Beijing National Laboratory for Molecular | Shaik S.,Hebrew University of Jerusalem | Yao J.,CAS Beijing National Laboratory for Molecular
Journal of Chemical Theory and Computation | Year: 2011

Gold-substrate interaction is essential in gold-catalyzed organic transformations. This study uses high-level coupled cluster calculations with core-valence correlation and complete basis set (CBS) limit extrapolation as a reference, for assessing the performance of popular density functional theory (DFT) approximations for a variety of Au(I)/Au(III) complexes with unsaturated aliphatic hydrocarbon CnHm substrates (ethene, ethyne, and allene). The tested functionals cover from LDA to GGA and meta-GGA, and to hybrids and double hybrids (LSDA, PBE, M06-L, TPSS, B3LYP, PBE0, M06, M06-2X, TPSSh, B2-PLYP, B2GP-PLYP). Both the geometry and bond dissociation energy (De) of the Au-CnHm complexes are studied. Our findings show that B2GP-PLYP, PBE0, and B2-PLYP are the best performing functionals for this set of Au-CnHm complexes. DFT dispersion correction (DFT-D3), though very helpful for some functionals (e.g., B3LYP and B2-PLYP), does not uniformly improve the results of all functionals. Ab initio methods like MP2 and SCSMP2 are also tested. MP2 is found to be the worst performing method, and while SCSMP2 greatly improves the results, still its accuracy is lower than that of the best functionals, B2GP-PLYP, PBE0, and B2-PLYP. © 2011 American Chemical Society.


Lai W.,Hebrew University of Jerusalem | Lai W.,Renmin University of China | Li C.,Hebrew University of Jerusalem | Chen H.,Hebrew University of Jerusalem | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2012

"Give us insight, not numbers" was Coulson's admonition to theoretical chemists. This Review shows that the valence bond (VB)-model provides insights and some good numbers for one of the fundamental reactions in nature, the hydrogen-atom transfer (HAT). The VB model is applied to over 50 reactions from the simplest H + H 2 process, to P450 hydroxylations and H-transfers among closed-shell molecules; for each system the barriers are estimated from raw data. The model creates a bridge to the Marcus equation and shows that H-atom abstraction by a closed-shell molecule requires a higher barrier owing to the additional promotion energy needed to prepare the abstractor for H-abstraction. Under certain conditions, a closed-shell abstractor can bypass this penalty through a proton-coupled electron transfer (PCET) mechanism. The VB model links the HAT and PCET mechanisms conceptually and shows the consequences that this linking has for H-abstraction reactivity. Give us insight and good numbers: Is it possible to understand one of the fundamental reactions in nature, the hydrogen-atom transfer (HAT), using a single unifying theory? The valence bond diagram model is such a unifying theory. It enables the barriers to be estimated from raw data (see plot), thereby creating a natural bridge to the Marcus equation, addresses the relationships between HAT to proton-coupled electron transfer (PCET), and shows how H-abstractions by closed-shell molecules can occur. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Huang Y.,CAS Beijing National Laboratory for Molecular | Guo X.,CAS Beijing National Laboratory for Molecular | Liu F.,University of Massachusetts Amherst | Huo L.,CAS Beijing National Laboratory for Molecular | And 5 more authors.
Advanced Materials | Year: 2012

A systematic molecular design process from PBDTTT-S to PBDTDTTT-S-T, a high-performance semiconducting polymer for organic photovoltaics, has been achieved by enhancing structural order, self-assembly and carrier mobility. Solar cells made from PBDTDTTT-S-T blended with PC 70BM show a power conversion efficiency (PCE) of 7.81%, which is 25% higher than that of the parent PBDTTT-S. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu M.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular | Xiao X.,CAS Beijing National Laboratory for Molecular | Xie Y.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Chemical Communications | Year: 2013

This communication describes a chiral base-catalyzed asymmetric [1,3]-proton shift of trifluoromethyl ketimines, giving a wide variety of trifluoromethyl aldimines containing various functional groups with up to 94% ee. © 2013 The Royal Society of Chemistry.


Zhan C.,CAS Beijing National Laboratory for Molecular | Li A.D.Q.,Washington State University
Current Organic Chemistry | Year: 2011

Perylene diimides (PDIs) have been playing important roles in several active fields. Therefore, we will first review the current methods to modify the skeleton of perylene diimides. Next, PDI self-assemblies and PDI folded nanostructures and chemically restrained PDI nanostructures are presented. Unusual physical properties due to nanostructures formation are discussed including the absorption band intensity reversal and π-stack red-fluorescence emission. Because of interesting π-stacked structures, PDI derivatives are considered as potential candidates for photovoltaic applications and organic electronics. More importantly, π-stacking can be tuned when the dihedral angle of the two naphthalene planes varies, thus resulting in adjusted interacting forces. Such cooperative forces lead to the discovery of molecular code phenomena, which will have profound impact an future bi-molecular reaction designs. © 2011 Bentham Science Publishers Ltd.


Ke D.,CAS Beijing National Laboratory for Molecular | Zhan C.,CAS Beijing National Laboratory for Molecular | Li A.D.Q.,Washington State University | Yao J.,CAS Beijing National Laboratory for Molecular
Angewandte Chemie - International Edition | Year: 2011

(Chemical Equation Presented) Tuning structures: Stimulus-responsive peptide self-assembly requires a balance of conformational change and structural continuity of stable β sheets. In an amphiphilic bipyridine-tripeptide model, temperature, and ultrasound switch a reversible morphological transformation between vesicles and nanofibers (see picture) through the synergistic effects of terminal β-sheet-forming peptides, flexible linkers, and rotatable bipyridine groups. © 2011 Wiley-VCH Verlag GmbH & Co. KGaA.


Shi H.,CAS Beijing National Laboratory for Molecular | Shi H.,Tianjin Polytechnic University | Zhao Y.,CAS Beijing National Laboratory for Molecular | Dong X.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Chemical Society Reviews | Year: 2013

Comb-like polymers with flexible side chains chemically pended onto a polymeric backbone afford some unusual properties due to their hierarchical structures, such as nanoscale confined crystallisation, phase transition and conformational variations, length scale effects, etc. Considerable attention has been paid to these featured polymers, regarding their importance in understanding the correlation between hierarchical structure and the assembled morphologies. In this review, we reviewed the recent research progress on the structure-property correlations of comb-like polymers. This article brings together and highlights the fabrication, structure determination and morphology characterization for comb-like polymers, especially for nanostructured packing patterns and frustrated mobility of chain segments from the selected examples. This journal is © The Royal Society of Chemistry.


Zhou P.,Wuhan University | Zhang Z.-G.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular | Chen X.,Wuhan University | Qin J.,Wuhan University
Chemistry of Materials | Year: 2014

A novel strong electron-acceptor, thieno[2,3-f]-2,1,3-benzothiadiazole-6- carboxylate (BTT), was first designed and synthesized. By introducing two thienyl groups into BTT and then copolymerizing with thienyl group substituted benzo[1,2-b:4,5-b′]dithiophene (BDTT) unit, a low band gap D-A copolymer (PBTT-TBDTT) was obtained. Compared with its polymer analogue (PBT-TBDTT) with benzothiadiazole (BT) as an acceptor, PBTT-TBDTT exhibits stronger intramolecular charge transfer. Thus, it shows much broader absorption covering almost the whole visible light region (in the range of 300-850 nm) and narrower optical band gap around 1.45 eV with a large IP (ionization potential) at 5.35 eV. The maximum efficiency of PBTT-TBDTT based device reaches 6.07% which is much higher than that of PBT-TBDTT (3.24%), indicating that BTT unit is a promising electron-acceptor moiety to construct low band gap D-A copolymers for PSCs with high photovoltaic performances. © 2014 American Chemical Society.


Huang D.,CAS Beijing National Laboratory for Molecular | Liu X.,CAS Beijing National Laboratory for Molecular | Li L.,CAS Beijing National Laboratory for Molecular | Cai Y.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Journal of the American Chemical Society | Year: 2013

An effective enantioselective bromoaminocyclization of allyl N-tosylcarbamates catalyzed by a chiral phosphine-Sc(OTf)3 complex is described. A wide variety of optically active oxazolidinone derivatives containing various functional groups can be obtained with high enantioselectivities. © 2013 American Chemical Society.


Zhang X.,Wuhan University | Yu L.,Wuhan University | Zhuang C.,Wuhan University | Peng T.,Wuhan University | And 2 more authors.
ACS Catalysis | Year: 2014

Highly asymmetric zinc phthalocyanine derivative (Zn-tri-PcNc) with intense near-IR light (650-800 nm) absorption is utilized as a sensitizer to extend the spectral response region of graphitic carbon nitride (g-C3N 4) from ∼450 nm to more than 800 nm. Ultraviolet-visible light (UV-vis) diffuse reflectance absorption spectra (DRS), photoluminescence (PL) spectra, time-resolved photoluminescence spectra (TRPS), and energy band structure analyses are adopted to investigate the photogenerated electron transfer process between Zn-tri-PcNc and g-C3N4 on both thermodynamics and dynamics aspects. After optimizing the photocatalytic condition and adding chenodeoxycholic acid (CDCA) as coadsorbent, Zn-tri-PcNc sensitized g-C3N4 photocatalyst shows a H2 production efficiency of 125.2 μmol h-1 under visible/near-IR- light (λ ≥ 500 nm) irradiation, corresponding to a turnover number (TON) of 5008 h-1 with an extremely high apparent quantum yield (AQY) of 1.85% at 700 nm monochromatic light irradiation. The present work should be the rarely fundamental investigation on the utilization of near-IR light of solar radiation for the photocatalytic H2 production from water splitting over a dye-sensitized semiconductor. © 2013 American Chemical Society.


Xiao X.,CAS Beijing National Laboratory for Molecular | Xie Y.,CAS Beijing National Laboratory for Molecular | Su C.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Journal of the American Chemical Society | Year: 2011

This paper describes an effective chiral base-catalyzed biomimetic transamination of α-keto esters using simple benzyl amines. A wide variety of α-amino esters containing various functional groups can be synthesized in high enantioselectivity and reasonable yield. © 2011 American Chemical Society.


Yu X.,CAS Beijing National Laboratory for Molecular | Zhang J.,CAS Beijing National Laboratory for Molecular | Choi W.,Samsung | Choi J.-Y.,Samsung | And 3 more authors.
Nano Letters | Year: 2010

Structural control, and especially chirality control, remains a significant challenge in the synthesis of single-walled carbon nanotubes (SWNTs). We report herein a rational approach to engineering fullerene caps for growing SWNTs with controlled structures via chemical vapor deposition (CVD). Opening of fullerendione via thermal oxidation yields hemispherical caps which can initiate SWNT growth at their open ends. The size and structure of these caps can be engineered by tuning the temperature of thermal oxidation. Results show that pregrowth treatment of the cap is indispensable to successful growth of SWNTs. The temperature used for thermal oxidation strongly affects the size and structure of the cap and further determines the diameter distribution of the as-grown SWNTs. Stronger oxidation treatments (450 °C oxidation in air) promote formation of thinner SWNTs, while weaker oxidation treatments (350 °C oxidation in air) lead to wider SWNTs. Interestingly, SWNTs made using fullerene caps show steplike diameter distributions relative to SWNTs catalyzed by Fe nanoparticles. This cap engineering using opened C60 provides a potential approach to grow SWNTs with controlled structures. © 2010 American Chemical Society.


Lai W.,Renmin University of China | Yao J.,CAS Beijing National Laboratory for Molecular | Shaik S.,Hebrew University of Jerusalem | Chen H.,CAS Beijing National Laboratory for Molecular
Journal of Chemical Theory and Computation | Year: 2012

Using the recently proposed corrective LCCSD(T) method as a reference, we systematically assess the widely used approximate density functionals to reproduce C-H bond activation barriers by pincer complexes of the late platinum group transition metals (TMs) (TM = Rh, Pd, Ir, Pt). The pincer ligands explored here cover a wide range of PNP, PCP, POCOP, NCN, and SCS types. Interestingly, B3LYP is found to be the most accurate functional, followed by several others previously identified as well-performing functionals, like B2GP-PLYP, B2-PLYP, and PBE0. However, all tested functionals were found to exhibit the following uniform trends: (1) the DFT barriers for reactions of group 9 TM (Rh and Ir) pincer complexes show higher accuracy compared with those for group 10 TM (Pd and Pt) reactions; (2) within the same group, 5d TM pincer complexes have higher accuracy than 4d TM ones. Consequently, the barriers for C-H activation by Pd(II) pincer complexes were found to be the least accurate among the four TMs in almost all functionals tested here. The DFT empirical dispersion correction (DFT-D3) is shown to have a very small effect on barrier height. This study has some implications for other Σ-bond activations like H-H, C-C, and C-halogen bonds by late platinum group pincer complexes. © 2012 American Chemical Society.


Peng T.,Wuhan University | Zhang X.,Wuhan University | Zeng P.,Wuhan University | Li K.,Wuhan University | Li X.,CAS Beijing National Laboratory for Molecular
Journal of Catalysis | Year: 2013

Carbon encapsulation strategy of Ni co-catalyst is applied to the fabrication of novel carbon-coated Ni (Ni@C)/CdS nanocomposite photocatalyst with high efficiency and good stability via a facile solvothermal process by using a pre-prepared Ni@C as a starting material. It is found that the metallic Ni nanoparticles encapsulated in the graphite-like carbon shells show a high chemical and thermal stability, and the resultant Ni@C/CdS nanocomposite shows an average photocatalytic H2-production activity of 622.7 μmol h-1 during 5-h visible-light irradiation and an apparent quantum yield up to ca. 20.5% under 420 nm monochromatic light irradiation. The metallic Ni in Ni@C acted as co-catalyst while the graphite-like carbon as CdS nanoparticles' support and electron acceptor, which resulting in the efficient charge separation, and then the enhanced photoactivity and stability for H 2 production as compared to the pristine CdS nanoparticles. The present novel carbon encapsulation strategy of Ni co-catalyst can shed light on the fabrication of new cheap photocatalyst with excellent photoactivity and stability for H2 production.© 2013 Elsevier Inc. All rights reserved.


Yan X.,Max Planck Institute of Colloids and Interfaces | Su Y.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular | Fruh J.,Max Planck Institute of Colloids and Interfaces | Mohwald H.,Max Planck Institute of Colloids and Interfaces
Angewandte Chemie - International Edition | Year: 2011

Riding the waves: An aldehyde triggers oriented long-range crystallization of self-assembling fibrous diphenylalanine peptide networks (see picture). The crystal growth is self-adjustable and likely subject to kinetic regulation, which leads to the 3D confinement of uniaxially oriented substructures in the resultant crystal. The peptide crystals exhibit remarkable thermal stability and optical waveguiding properties. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu H.,CAS Beijing National Laboratory for Molecular | Du D.-M.,Beijing Institute of Technology | Du D.-M.,CAS Beijing National Laboratory for Molecular
Advanced Synthesis and Catalysis | Year: 2010

The new diphenylamine-linked bis(imidazoline) ligands were prepared through Kelly-You's imidazoline formation procedure mediated by Hendrickson 's reagent in good yields. The novel ligands were tested in the asymmetric Friedel-Crafts alkylation of indole derivatives with nitroalkenes. In most cases, good yields (up to 97%) and excellent enantioselectivities (up to 98%) can be achieved. The optimized bis(imidazoline) ligand with trans-diphenyl substitution on the imidazoline ring gave better enantioselectivity than the corresponding bis(oxazoline) ligand. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA,.


Zhang X.,Beijing Institute of Technology | Zhang X.,CAS Beijing National Laboratory for Molecular | Li Y.,Beijing Institute of Technology | Cao C.,Beijing Institute of Technology
Journal of Materials Chemistry | Year: 2012

Mesoporous silica/carbon nanomaterials with various hierarchical structures have been fabricated by a one-pot approach. Polymer/silica/surfactant (PSS) composites are first prepared by the co-sol-gel process of TEOS and resorcinol-formaldehyde precursor in the presence of CTAB. The PSS morphologies could be tuned by simply altering the content of ethanol in solution. © 2012 The Royal Society of Chemistry.


Zhang Z.,CAS Beijing National Laboratory for Molecular | Zhang Z.,Shandong Polytechnic University | Zhang X.,CAS Beijing National Laboratory for Molecular | Xin Z.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Advanced Materials | Year: 2013

Conductive patterns with line widths of 5-10 μm are successfully fabricated by utilizing the coffee-ring effect in inkjet printing, resulting in transmittance values of up to 91.2% in the visible to near-infrared region. This non-lithographic approach broadens the range of fabrication procedures that can be used to create various nanoparticle-based microstructures and electronic devices. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan X.,Max Planck Institute of Colloids and Interfaces | Blacklock J.,Max Planck Institute of Colloids and Interfaces | Li J.,CAS Beijing National Laboratory for Molecular | Mohwald H.,Max Planck Institute of Colloids and Interfaces
ACS Nano | Year: 2012

Figure Persented: We present a general strategy to create polypeptide-gold nanoconjugates by a one-pot synthesis approach, where polypeptides act not only as capping agents but also as reductants for the formation of gold nanoparticles without the need of an additional reducing agent. The present approach is environmentally benign, facile, and flexible for the design of functional polypeptide-gold nanoconjugates. As a demonstration of as-synthesized nanoconjugates for biomedical applications, the resulting positively charged polypeptide-conjugated gold nanoparticles are applied for gene delivery. A gradual and prolonged intracellular uptake and transfection is achieved, and transfection activity is maintained for almost two weeks with no obvious cytotoxicity. The biologically based method presented in this work will provide a new alternative in creating a variety of multifunctional polypeptide-metallic nanoconjugates in a simple and straightforward manner, which will be more advantageous for their applications in biomedicine. © 2011 American Chemical Society.


Yan X.,Max Planck Institute of Colloids and Interfaces | Li J.,CAS Beijing National Laboratory for Molecular | Mohwald H.,Max Planck Institute of Colloids and Interfaces
Advanced Materials | Year: 2012

3D hybrid colloidal spheres with integrated functions and collective properties are fabricated using a variety of common inorganic nano-objects as building blocks in association with polyelectrolyte encapsulation through a facile template strategy. The fabrication strategy is generally suited for design of functional colloidal spheres in a simple and controllable manner, and thus opens a new avenue for developing hybrid materials with multiple functions and collective properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu H.,CAS Beijing National Laboratory for Molecular | Du D.-M.,CAS Beijing National Laboratory for Molecular | Du D.-M.,Beijing Institute of Technology
European Journal of Organic Chemistry | Year: 2010

A diphenylamine-linked bis(oxazoline) ligand with trans-diphenyl substitution on the oxazoline rings has been immobilized onto one- to three-generation Fréchet-type dendrimers and a C3-symmetric core structure. The catalytic activities and enantioselectivities of these new ligands were tested in the asymmetric Friedel-Crafts alkylation reactions of indole derivatives with, nitroalkenes. The two types of immobilized ligands exhibited similar enantioselectivities and substrate compatibilities to the free ligand trans-DPBO we reported previously. No dendrimer effect was observed in the kinetic investigation of the Fréchet-type dendrimer-immobilized ligands. The in situ recycling of the catalysts was also tested to illustrate the effect of reducing catalyst loading and the efficiency of our system. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.


Zou Q.,CAS Institute of Process Engineering | Zhang L.,Max Planck Institute of Colloids and Interfaces | Yan X.,CAS Institute of Process Engineering | Wang A.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2014

Photocatalytically active, multi-chambered, biomolecule-based microspheres were prepared by hierarchical co-assembly of simple dipeptides and porphyrins. The colloidal microspheres are highly hydrated and consist of a network of J-aggregate nanoscale substructures that serve as light-harvesting antennae with a relatively broad spectral cross-section and considerable photostability. These optical properties can be exploited in photocatalytic reactions involving inorganic or organic species. Taken together, these structural and functional features suggest that soft porous biomolecule-based colloids are a plausible photosynthetic model that could be developed towards demonstrating aspects of primitive abiotic cellularity. Simple but multifunctional: Photocatalytically active microspheres with highly hydrated, accessible multi-chambered interiors have been prepared by cooperative self-assembly of simple dipeptides and porphyrins (see picture). They serve as a plausible photosynthetic model that could be potentially developed towards studying aspects of primitive abiotic cellularity. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan X.,CAS Beijing National Laboratory for Molecular | Yan X.,Max Planck Institute of Colloids and Interfaces | Zhu P.,CAS Beijing National Laboratory for Molecular | Fei J.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2010

(Figure Presented) Versatile hybrid colloidal spheres, selfassembled through the association of cationic peptide and polyoxometalate clusters, are not only responsive towards external stimuli but also show novel, adaptive inclusion properties. The adaptive nature of hybrid colloidal spheres is utilized to encapsulate a wide variety of guest materials ranging from watersoluble molecules to hydrophobic nanoparticles and hydrophilic inorganic nanoparticles. © 2010 WILEY-VCH Verlag GmbH &, Co. KGaA.


Anthony J.E.,University of Kentucky | Facchetti A.,Polyera Corporation | Heeney M.,Imperial College London | Marder S.R.,Georgia Institute of Technology | Zhan X.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2010

Organic semiconductors have been the subject of intensive academic and commercial interest over the past two decades, and successful commercial devices incorporating them are slowly beginning to enter the market. Much of the focus has been on the development of hole transporting, or p-type, semiconductors that have seen a dramatic rise in performance over the last decade. Much less attention has been devoted to electron transporting, or so called n-type, materials, and in this paper we focus upon recent developments in several classes of n-type materials and the design guidelines used to develop them. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.


Zhang Y.,CAS Institute of Chemistry | Yuan X.,CAS Institute of Chemistry | Wang Y.,CAS Institute of Chemistry | Chen Y.,CAS Institute of Chemistry | And 2 more authors.
Journal of Materials Chemistry | Year: 2012

A one-step photochemical approach was established to quickly and specifically synthesize uniformly dispersed silver nanoparticles (AgNPs) on reduced graphene oxide (rGO) nanosheets. Silver-ammonia and graphene oxide (GO) were used as precursors to enhance the coordination-based adsorption of silver cations onto the negatively charged GO surface through ligation with ammonia, which could also continuously stabilize the nucleation and growth of AgNPs. The method allowed the easy control of the coverage percentage of AgNPs on rGO in a range from 7.2% to 81.6%. The prepared AgNPs-rGO composites were highly dispersible and stable in water in the absence of any stabilizing agent, and showed excellent catalytic properties in the reduction of 2-nitroaniline to 1,2-benzenediamine. © 2012 The Royal Society of Chemistry.


Du X.,Beijing Institute of Technology | Liu H.,CAS Beijing National Laboratory for Molecular | Du D.-M.,Beijing Institute of Technology
European Journal of Organic Chemistry | Year: 2011

Diphenyl sulfide linked bis(imidazoline) ligands with electron-withdrawing N-Ts substitution and electron-donating N-alkyl or N-H substitutions were synthesized through different routes. The electronic effects of the ligands were tuned rationally, and dramatic variation in their catalytic behavior was observed. N-Alkyl and N-H ligands demonstrated much higher catalytic activity and improved enantioselectivity than N-Ts ligands in Pd-catalyzed asymmetric allylic alkylation reactions. Diphenyl sulfide linked bis(imidazoline) ligands were synthesized. The electronic effects of the ligands were tuned rationally, and dramatic variation in their catalytic behavior was observed. N-Alkyl and N-H ligands showed much higher catalytic activity and improved enantioselectivity over N-Ts ligands in Pd-catalyzed asymmetric allylic alkylation reactions. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan X.,Max Planck Institute of Colloids and Interfaces | Yan X.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular | Mohwald H.,Max Planck Institute of Colloids and Interfaces
Advanced Materials | Year: 2011

Hexagonal peptide microtubes are spontaneously formed upon solvent thermal annealing. They have diameters on the order of micrometers and reach several millimeters in length. The microtubes evolve hierarchically in a hexagonal packing pattern from the molecular level to the micrometer scale. Such crystalline peptide microtubes serve as an active optical waveguide, allowing for light propagation along the long axis. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yang W.,Beijing Institute of Technology | Liu H.,CAS Beijing National Laboratory for Molecular | Du D.-M.,Beijing Institute of Technology
Organic and Biomolecular Chemistry | Year: 2010

A combinatorial in situ three-component chiral oxazoline-Schiff base copper(ii) complex catalyst formation method was developed. This simple combinatorial chiral catalyst approach provided a modular library of chiral oxazoline-Schiff base copper(ii) complex catalysts. The catalytic activity of these in situ generated catalysts can be rapidly and conveniently evaluated in the asymmetric Henry reaction. Moderate to good yields and enantioselectivities (up to 92% ee) were obtained under the optimized condition. The combination of modular three-component catalyst formation and in situ asymmetric reaction provides a new technology in asymmetric catalysis. © 2010 The Royal Society of Chemistry.


Cao F.-F.,CAS Beijing National Laboratory for Molecular | Deng J.-W.,Leibniz Institute for Solid State and Materials Research | Xin S.,CAS Beijing National Laboratory for Molecular | Ji H.-X.,Leibniz Institute for Solid State and Materials Research | And 4 more authors.
Advanced Materials | Year: 2011

Well-organized Si-Cu nanocables are directly anchored on a current collector to promote the cycling stability and high rate capability of Si as a superior anode in lithium-ion batteries. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan X.,CAS Beijing National Laboratory for Molecular | Yan X.,Max Planck Institute of Colloids and Interfaces | Zhu P.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular
Chemical Society Reviews | Year: 2010

Micro- and nanostructures fabricated from biological building blocks have attracted tremendous attention owing to their potential for application in biology and in nanotechnology. Many biomolecules, including peptides and proteins, can interact and self-assemble into highly ordered supramolecular architectures with functionality. By imitating the processes where biological peptides or proteins are assembled in nature, one can delicately design and synthesize various peptide building blocks composed of several to dozens of amino acids for the creation of biomimetic or bioinspired nanostructured materials. This tutorial review aims to introduce a new kind of peptide building block, the diphenylalanine motif, extracted with inspiration of a pathogenic process towards molecular self-assembly. We highlight recent and current advances in fabrication and application of diphenylalanine-based peptide nanomaterials. We also highlight the preparation of such peptide-based nanostructures as nanotubes, spherical vesicles, nanofibrils, nanowires and hybrids through self-assembly, the improvement of their properties and the extension of their applications. © The Royal Society of Chemistry 2010.


Feng L.,Shanxi University | Feng L.,CAS Beijing National Laboratory for Molecular | Liu L.,CAS Beijing National Laboratory for Molecular | Lv F.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Advanced Materials | Year: 2014

Multicolor conjugated polymer nanoparticles (CPNs) are designed and biofunctionalized with antibody for targeted cell imaging and cell detection. In comparison to single-antibody recognition mode to tumor cells, enhanced specificity for targeted imaging and detection of tumor cells is achieved by binding two antibody functionalized CPNs to one tumor cell. This strategy provides a new platform for designing CPNs useful for targeted imaging, cells detection and other biological applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Feng L.,CAS Beijing National Laboratory for Molecular | Feng L.,Shanxi University | Zhu C.,CAS Beijing National Laboratory for Molecular | Yuan H.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Chemical Society Reviews | Year: 2013

In the past few years, conjugated polymer nanoparticles (CPNs) have been successfully prepared and applied in the biological field because of their unique opto-electronic properties. The rapid development of CPNs is mainly attributed to their simple synthesis procedures and easy separation steps. The advantages of CPNs include high brightness, excellent photostability, low cytotoxicity, high quantum yield and versatile surface modification. The functionalization of CPNs with specific recognition elements imparts them good ability for targeted recognition and imaging in vitro and in vivo. CPNs can be applied to deliver drug and gene, and simultaneously to real-time monitor the release process due to their self-luminous characteristics. Moreover, CPNs can sensitize oxygen molecules to generate reactive oxygen species (ROS) which can kill adjacent bacteria and tumor cells. In this tutorial review, we provide a recent development of the preparation methods, properties, and functionalization strategies of CPNs, especially discussing their biological applications in targeted imaging, drug/gene delivery and biomedicine. The challenges and outlooks in this field will also be discussed. © 2013 The Royal Society of Chemistry.


Chen X.,University of Missouri - Kansas City | Liu L.,CAS Changchun Institute of Optics and Fine Mechanics and Physics | Huang F.,CAS Beijing National Laboratory for Molecular | Huang F.,CAS Shanghai Institute of Ceramics
Chemical Society Reviews | Year: 2015

In the past few decades, there has been a wide research interest in titanium dioxide (TiO2) nanomaterials due to their applications in photocatalytic hydrogen generation and environmental pollution removal. Improving the optical absorption properties of TiO2 nanomaterials has been successfully demonstrated to enhance their photocatalytic activities, especially in the report of black TiO2 nanoparticles. The recent progress in the investigation of black TiO2 nanomaterials has been reviewed here, and special emphasis has been given on their fabrication methods along with their various chemical/physical properties and applications. This journal is © The Royal Society of Chemistry.


Zhang C.,Tianjin University | Chen P.,Tianjin University | Chen P.,CAS Beijing National Laboratory for Molecular | Hu W.,Tianjin University | Hu W.,CAS Beijing National Laboratory for Molecular
Chemical Society Reviews | Year: 2015

Organic field-effect transistors (OFETs) are one of the key components of modern organic electronics. While the past several decades have witnessed huge successes in high-performance OFETs, their sophisticated functionalization with regard to the responses towards external stimulations has also aroused increasing attention and become an important field of general concern. This is promoted by the inherent merits of organic semiconductors, including considerable variety in molecular design, low cost, light weight, mechanical flexibility, and solution processability, as well as by the intrinsic advantages of OFETs including multiparameter accessibility and ease of large-scale manufacturing, which provide OFETs with great potential as portable yet reliable sensors offering high sensitivity, selectivity, and expeditious responses. With special emphases on the works achieved since 2009, this tutorial review focuses on OFET-based gas sensors. The working principles of this type of gas sensors are discussed in detail, the state-of-the-art protocols developed for high-performance gas sensing are highlighted, and the advanced gas discrimination systems in terms of sensory arrays of OFETs are also introduced. This tutorial review intends to provide readers with a deep understanding for the future design of high-quality OFET gas sensors for potential uses. © 2015 The Royal Society of Chemistry.


Ling X.,University of Science and Technology Beijing | Xie L.,University of Science and Technology Beijing | Fang Y.,University of Science and Technology Beijing | Xu H.,CAS Beijing National Laboratory for Molecular | And 6 more authors.
Nano Letters | Year: 2010

Graphene is a monolayer of carbon atoms packed into a two-dimensional (2D) honeycomb crystal structure, which is a special material with many excellent properties. In the present study, we will discuss the possibility that graphene can be used as a substrate for enhancing Raman signals of adsorbed molecules. Here, phthalocyanine (Pc), rhodamine 6G (R6G), protoporphyin IX (PPP), and crystal violet (CV), which are popular molecules widely used as a Raman probe, are deposited equally on graphene and a SiO2/Si substrate using vacuum evaporation or solution soaking. By comparing the Raman signals of molecules on monolayer graphene and on a SiO2Si substrate, we observed that the intensities of the Raman signals on monolayer graphene are much stronger than on a SiO2/Si substrate, indicating a clear Raman enhancement effect on the surface of monolayer graphene. For solution soaking, the Raman signals of the molecules are visible even though the concentration is low to 10-8 mol/L or less. What's more interesting, the enhanced efficiencies are quite different on monolayer, few-layer, multilayer graphene, graphite, and highly ordered pyrolytic graphite (HOPG). The Raman signals of molecules on multilayer graphene are even weaker than on a SiO2/Si substrate, and the signals are even invisible on graphite and HOPG. Taking the Raman signals on the SiO2/Si substrate as a reference. Raman enhancement factors on the surface of monolayer graphene can be obtained using Raman Intensity ratios. The Raman enhancement factors are quite different for different peaks, changing from 2 to 17. Furthermore, we found that the Raman enhancement factors can be distinguished through three classes that correspond to the symmetry of vibrations of the molecule. We attribute this enhancement to the charge transfer between graphene and the molecules, which result in a chemical enhancement. This is a new phenomenon for graphene that will expand the application of graphene to microanalysis and is good for studying the basic properties of both graphene and SERS. © 2010 American Chemical Society.


Sun Y.,CAS Beijing National Laboratory for Molecular | Sun Y.,Beijing University of Chemical Technology | Cui C.,CAS Beijing National Laboratory for Molecular | Wang H.,Beijing University of Chemical Technology | Li Y.,CAS Beijing National Laboratory for Molecular
Advanced Energy Materials | Year: 2012

The photovoltaic properties of poly(3-pentylthiophene) (P3PT) are studied. P3PT-based polymer solar cells with IC 60BA and IC 70BA as acceptors demonstrate high power conversion efficiencies of 4.50% and 5.44% with high open-circuit voltages of 0.89 and 0.88 V, respectively. These devices benefit from the high-lying LUMO energy levels of IC 60BA and IC 70BA. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Chen W.,Zhejiang University | Han C.,Second Military Medical University | Xie B.,Zhejiang University | Hu X.,CAS Beijing National Laboratory for Molecular | And 10 more authors.
Cell | Year: 2013

RIG-I is a critical RNA virus sensor that serves to initiate antiviral innate immunity. However, posttranslational regulation of RIG-I signaling remains to be fully understood. We report here that RNA viruses, but not DNA viruses or bacteria, specifically upregulate lectin family member Siglecg expression in macrophages by RIG-I- or NF-κB-dependent mechanisms. Siglec-G-induced recruitment of SHP2 and the E3 ubiquitin ligase c-Cbl to RIG-I leads to RIG-I degradation via K48-linked ubiquitination at Lys813 by c-Cbl. By increasing type I interferon production, targeted inactivation of Siglecg protects mice against lethal RNA virus infection. Taken together, our data reveal a negative feedback loop of RIG-I signaling and identify a Siglec-G-mediated immune evasion pathway exploited by RNA viruses with implication in antiviral applications. These findings also provide insights into the functions and crosstalk of Siglec-G, a known adaptive response regulator, in innate immunity. © 2013 Elsevier Inc.


Tang P.,CAS Beijing National Laboratory for Molecular | Zhu Q.,China National Institute of Clean and Low Carbon Energy | Wu Z.,CAS Beijing National Laboratory for Molecular | Ma D.,CAS Beijing National Laboratory for Molecular
Energy and Environmental Science | Year: 2014

The conversion of methane to more valuable chemicals is one of the most intensively studied topics in catalysis. The direct conversion of methane is attractive because the process is simple, but unfortunately its products are chemicals that are more reactive than methane. The current status of this research field is discussed with an emphasis on C-H bond activation and future challenges. This journal is © the Partner Organisations 2014.


Wang H.,CAS Technical Institute of Physics and Chemistry | Wang H.,University of Chinese Academy of Sciences | Xie L.,Beijing University of Chemical Technology | Peng Q.,CAS Beijing National Laboratory for Molecular | And 5 more authors.
Advanced Materials | Year: 2014

Thermally activated delayed fluorescence emitters with small energy gap between the triplet and singlet (ΔEST), TXO-PhCz and TXO-TPA, have been successfully synthesized by combining a hole-transporting TPA/PhCz moiety and an electron-transporting TXO moiety. Both compounds display efficient solid-state luminescence with an efficient up-conversion of the triplet to singlet. OLEDs based on them exhibt high performance up to 21.5%, which is among the best reported for OLEDs. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang B.,Beijing University of Chemical Technology | Wang J.,CAS Beijing National Laboratory for Molecular | Zhang X.,Beijing University of Chemical Technology
Langmuir | Year: 2013

We used the lattice Boltzmann method to investigate how the hierarchical structure of a rough solid surface, which in this work is modeled as the microstructure (micropillars) covered with nanostructures (nanopillars), affects the contact angle of microdroplets atop of the solid surface and the wetting transition between the Wenzel and Cassie states. Our simulation results show that the Wenzel-to-Cassie state transition can be achieved by decreasing the fluid-solid attraction, increasing the micropillar spacing, or coating the microstructures with nanostructures. For the effect of the hierarchical structure on the contact angle, we find that the micropillars show a negligible effect on the contact angle, but they may affect the sliding angle. In contrast, it is the nanostructure that determines the contact angle. The contact angle increases with the nanopillar length until reaching a maximal value, but its dependence on the nanopillar spacing becomes more complicated. The contact angle may first increase with the nanopillar spacing and then decreases, or decreases monotonously, depending on whether the liquid enters the nanostructure or not. In this work, we also demonstrate in the presence of contact line pinning, that the pinning effect affects the apparent contact angle. © 2013 American Chemical Society.


Feng X.,CAS Beijing National Laboratory for Molecular | Wang Y.,CAS Beijing National Laboratory for Molecular | Wei B.,Beijing University of Chemical Technology | Yang J.,Beijing University of Chemical Technology | Du H.,CAS Beijing National Laboratory for Molecular
Organic Letters | Year: 2011

A variety of N-sulfinyl-based chiral sulfur-olefin ligands has been successfully developed for the first time for rhodium-catalyzed highly efficient and enantioselective 1,4-additions. The ease of synthesis and needless consideration of the carbon chirality makes this novel type of ligands attractive for asymmetric catalysis. © 2011 American Chemical Society.


Qian C.,Second Military Medical University | Cao X.,Second Military Medical University | Cao X.,CAS Beijing National Laboratory for Molecular
Annals of the New York Academy of Sciences | Year: 2013

Toll-like receptors (TLRs) are critical pattern recognition receptors (PRRs) that recognize pathogen-associated molecular patterns (PAMPs), which are conserved and specific molecular "signatures" expressed by pathogens. TLR ligation triggers distinct but shared signaling pathways that lead to effector mechanisms in innate immune responses. TLR specificity and activation are strictly and finely tuned at multiple levels of various signal transduction pathways, resulting in complex signaling platforms. Many molecules, ranging from membrane and cytosol to nuclear, contribute to TLR ligand discrimination or receptor signaling and play different roles in the regulation of TLR responses via different mechanisms, such as cross-regulation, protein modification, helper cofactors, and posttranscriptional and epigenetic regulation. Herein, we summarize the most recent literature that provides new insight into regulation of TLR signaling-triggered innate immune responses. A greater understanding of the mechanisms underlying the control of TLR signaling may provide new targets for therapeutic intervention for infections and inflammatory diseases. © 2012 The New York Academy of Sciences.


Ke J.,CAS Beijing National Laboratory for Molecular | Xiao J.-W.,CAS Beijing National Laboratory for Molecular | Zhu W.,CAS Beijing National Laboratory for Molecular | Liu H.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Journal of the American Chemical Society | Year: 2013

Active center engineering at atomic level is a grand challenge for catalyst design and optimization in many industrial catalytic processes. Exploring new strategies to delicately tailor the structures of active centers and bonding modes of surface reactive intermediates for nanocatalysts is crucial to high-efficiency nanocatalysis that bridges heterogeneous and homogeneous catalysis. Here we demonstrate a robust approach to tune the CO oxidation activity over CeO2 nanowires (NWs) through the modulation of the local structure and surface state around LnCe′ defect centers by doping other lanthanides (Ln), based on the continuous variation of the ionic radius of lanthanide dopants caused by the lanthanide contraction. Homogeneously doped (110)-oriented CeO2:Ln NWs with no residual capping agents were synthesized by controlling the redox chemistry of Ce(III)/Ce(IV) in a mild hydrothermal process. The CO oxidation reactivity over CeO2:Ln NWs was dependent on the Ln dopants, and the reactivity reached the maximum in turnover rates over Nd-doped samples. On the basis of the results obtained from combined experimentations and density functional theory simulations, the decisive factors of the modulation effect along the lanthanide dopant series were deduced as surface oxygen release capability and the bonding configuration of the surface adsorbed species (i.e., carbonates and bicarbonates) formed during catalytic process, which resulted in the existence of an optimal doping effect from the lanthanide with moderate ionic radius. © 2013 American Chemical Society.


Feng X.,CAS Beijing National Laboratory for Molecular | Nie Y.,Beijing University of Chemical Technology | Yang J.,Beijing University of Chemical Technology | Du H.,CAS Beijing National Laboratory for Molecular
Organic Letters | Year: 2012

This paper describes a Rh(I)-catalyzed highly efficient and enantioselective 1,2-addition of arylboronic acids to α-diketones with the use of a simple sulfur-alkene hybrid ligand. With as low as a 0.1 mol % catalyst loading, a variety of optically active α-hydroxyketones can be furnished in high yields with excellent ee's. © 2012 American Chemical Society.


Wan Y.,CAS Beijing National Laboratory for Molecular | Gan Z.,Beijing University of Chemical Technology | Li Z.,CAS Beijing National Laboratory for Molecular
Polymer Chemistry | Year: 2014

Poly(ethylene oxide)-block-poly(ε-caprolactone) (PEG-b-PCL) copolymers with three kinds of terminal functional groups (amino, carboxyl and methoxyl) at the hydrophilic block end were synthesized via sequential ring-opening polymerization (ROP). Their structures were characterized by GPC and 1H NMR. Micelles prepared from these copolymers showed different surface charge properties. The enzymatic degradation behaviour of these charged micelles in PBS (pH 7.0) was investigated using DLS, UV and TEM. BSA was used as a model protein to simulate the interactions between charged micelles and plasma components. It was found that micelles with different surface charges showed distinct degradation behaviour using lipase PS as the enzyme and different stability in the presence of BSA. Micelles with a neutral surface group showed a slow and partial degradation, while charged micelles showed a quick and complete degradation. We found that the nature of interactions between charged micelles and proteins was critical to the stability of polymeric micelles in vitro. © 2014 The Royal Society of Chemistry.


Zhang W.,CAS Suzhou Institute of Nano Technology and Nano Bionics | Zhu Y.,CAS Suzhou Institute of Nano Technology and Nano Bionics | Liu X.,CAS Suzhou Institute of Nano Technology and Nano Bionics | Wang D.,CAS Suzhou Institute of Nano Technology and Nano Bionics | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2014

Conventional polymer membranes suffer from low flux and serious fouling when used for treating emulsified oil/water mixtures. Reported herein is the fabrication of a novel superhydrophilic and underwater superoleophobic poly(acrylic acid)-grafted PVDF filtration membrane using a salt-induced phase-inversion approach. A hierarchical micro/nanoscale structure is constructed on the membrane surface and endows it with a superhydrophilic/ underwater superoleophobic property. The membrane separates both surfactant-free and surfactant-stabilized oil-in-water emulsions under either a small applied pressure (<0.3 bar) or gravity, with high separation efficiency and high flux, which is one to two orders of magnitude higher than those of commercial filtration membranes having a similar permeation property. The membrane exhibits an excellent antifouling property and is easily recycled for long-term use. The outstanding performance of the membrane and the efficient, energy and cost-effective preparation process highlight its potential for practical applications. Salting away: The title membranes having different PAA graft ratios were fabricated by using a salt-induced phase-inversion process. The membrane can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions under either a small applied pressure (0.1 bar) or gravity, with a high separation efficiency and high flux. CA=contact angle. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Shang H.,CAS Beijing National Laboratory for Molecular | Shang H.,University of Chinese Academy of Sciences | Shang H.,Handan College | Fan H.,CAS Beijing National Laboratory for Molecular | And 6 more authors.
Advanced Materials | Year: 2011

A new 3D, star-shaped, donor-acceptor-donor (D-A-D) small molecule with triphenylamine as the core and donor unit, benzothiadiazole as the bridge and acceptor unit, and hexylterthiophene as the arm and donor unit is synthesized. Photovoltaic devices based on the blend of this compound and [6,6]-phenyl-C 71-butyric-acid-methyl-ester (PC71BM) exhibited power conversion efficiencies as high as 4.3%, which is among the highest reported for solution-processed organic solar cells based on small molecules. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li Y.-X.,CAS Beijing National Laboratory for Molecular | Xuan Q.-Q.,CAS Beijing National Laboratory for Molecular | Liu L.,CAS Beijing National Laboratory for Molecular | Wang D.,CAS Beijing National Laboratory for Molecular | And 2 more authors.
Journal of the American Chemical Society | Year: 2013

A direct dehydrative coupling of terminal alkynes with allylic alcohols catalyzed by Pd(PPh3)4 with an N,P-ligand assisted by Ti(OiPr)4 has been developed. The coupling reaction tolerates various functional groups, providing a valuable synthetic tool to access 1,4-enynes. © 2013 American Chemical Society.


Liu T.-F.,CAS Fujian Institute of Research on the Structure of Matter | Zhang W.,CAS Beijing National Laboratory for Molecular | Sun W.-H.,CAS Beijing National Laboratory for Molecular | Cao R.,CAS Fujian Institute of Research on the Structure of Matter
Inorganic Chemistry | Year: 2011

A conjugated ligand, 2-(carboxylic acid)-6-(2-benzimidazolyl) pyridine (Hcbmp), and a series of Lanthanide metal-organic frameworks (MOFs) [Ln 2(cbmp)(ox)3(H2O)2]2 ̇ 2H3O+ ̇ 7H2O(Ln = Sm(3), Eu (4), and Gd (5),H2ox = oxalic acid) have been designed and assembled. To elucidate how the conjugated ligands modulate the structures and luminescence properties, we carried out the structural characterizations and luminescence studies of complexes 3 and 4, and their corresponding oxalate complexes [Ln(ox)1.5(H2O)3] ̇ 2H2O (Ln = Sm (1) and Eu (2)) were also investigated for comparison. The changes of luminescence behaviors upon dehydration and D2O-rehydration processes are presented and discussed in detail. The results indicated that, the cbmp - ligands distribute on both sides of the ox--Ln bilayer network to construct a sandwich structure. Moreover, the lowest triplet state of cbmp - ligands can match well the energy levels of the Sm3+ and Eu3+ cations which allow the preparation of new Ln-MOF materials with enhanced luminescence properties. Meanwhile, the crystallinity of solid states produces more substantial change in the luminescence behaviors than removal or replacement of effective nonradiative relaxers. © 2011 American Chemical Society.


Zhong H.,University of Toronto | Lo S.S.,University of Toronto | Mirkovic T.,University of Toronto | Li Y.,Beijing Normal University | And 3 more authors.
ACS Nano | Year: 2010

CuInS2 nanocrystals are viewed as very good candidates for solar harvesting and light emitting applications. Here we report an optimized noninjection method for the synthesis of monodisperse pyramidal CuInS 2 nanocrystals with sizes ranging from 3 to 8 nm. This synthetic route is able to yield large amounts of high quality nanoparticles, usually in the gram scale for one batch experiment. The structure and surface studies showed that the resulting nanocrystals are pyramids of CuInS2 tetragonal phase with well-defined facets, while their surface is functionalized with dodecanethiol capping ligands. Spectroscopic and electrochemical measurements revealed size-dependent optical and electrical properties of CuInS2 nanocrystals, demonstrating quantum confinement effects in these systems. The size-dependent optical bandgaps of CuInS2 nanocrystals were found to be consistent with the finite-depth well effective mass approximation (EMA) calculations, which provide a convenient method to estimate the diameter of CuInS2 pyramids. Additionally we have also determined some important physical parameters, including bandgaps and energy levels, for this system, which are crucial for the integration of CuInS 2 nanocrystals in potential device applications. © 2010 American Chemical Society.


Xia D.,CAS Beijing National Laboratory for Molecular | Wang Y.,Northwest University, China | Du Z.,Northwest University, China | Zheng Q.-Y.,CAS Beijing National Laboratory for Molecular | Wang C.,CAS Beijing National Laboratory for Molecular
Organic Letters | Year: 2012

An efficient rhenium-catalyzed site-switchable addition of indoles to terminal alkynes is described. A variety of bisindolylalkane derivatives are expeditiously synthesized in high yields with excellent regioselectivity. Preliminary mechanistic study sheds light on the observed regiodivergent addition. © 2011 American Chemical Society.


Liu L.,CAS Beijing National Laboratory for Molecular | Yu M.,CAS Beijing National Laboratory for Molecular | Wayland B.B.,Temple University | Fu X.,CAS Beijing National Laboratory for Molecular
Chemical Communications | Year: 2010

Selective oxidation of alcohol in water using molecular oxygen as the terminal oxidant is mediated by rhodium porphyrin complexes. Addition of methanol to an aqueous solution of (TSPP)Rh(iii) resulted in observation of the key intermediate porphyrin rhodium(iii) methoxide species. The activation parameters for βC-H elimination of Rh-alkoxide were evaluated. © 2010 The Royal Society of Chemistry.


Ni J.,Suzhou University | Li Y.,CAS Beijing National Laboratory for Molecular
Advanced Energy Materials | Year: 2016

Carbon nanomaterials including fullerenes, carbon nanotubes, graphene, and their assemblies represent a unique type of materials in diverse formats and dimensions. They feature a large surface area, superior conductivity, fast charge transport, and intrinsic stability, which are essentially required for vari-ous electrochemical energy storage (EES) systems such as Li-ion batteries, supercapacitors, and redox flow cells. The scaled-up and reliable production and assembly of carbon nanomaterials is a prerequisite for the development of carbon nanomaterial-based EES devices. In this progress report, the preparation of carbon nanostructures and the state-of-the-art applications of carbon nanomaterials with different dimensions in versatile EES systems are summarized. The importance of the synergetic effect induced by interactions between nanocarbons and active electrode species is highlighted. The main challenges and prospects in this field are also discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Chen L.,Fudan University | Du R.,CAS Beijing National Laboratory for Molecular | Zhang J.,CAS Beijing National Laboratory for Molecular | Yi T.,Fudan University
Journal of Materials Chemistry A | Year: 2015

Large-scale manipulation of the density (from 2.5 to 1327 mg cm-3) and wettability of carbon-based aerogels has been realized by delicately modulating the gelation, drying and post-treatment processes. An unexpected "Janus face" effect of pyrrole was revealed in the fabrication process. Pyrrole acts as a "spacer" at relatively low concentrations (ca. 5 vol%), leading to an increase of the aerogel density. By using systematic studies, the oil adsorption capacity of aerogels has been correlated with the aerogel density and surface wettability, which can guide the production of highly efficient sorbents. For example, a polydimethylsiloxane modified graphene nanoribbons aerogel with a density of 2.5 mg cm-3 was prepared and showed a remarkable adsorption capacity of up to 302 times for phenixin and 121 times for n-hexane its own weight, much higher than that of most carbonaceous sorbents previously reported. Furthermore, a proof-of-concept aerogel-based floating-type densitometer has also been proposed to expand the potential applications of aerogels. © The Royal Society of Chemistry.


Changshui H.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular | Song Y.,CAS Beijing National Laboratory for Molecular | Song Y.,Suzhou University | And 2 more authors.
Advanced Materials | Year: 2010

Using the small molecule TEOP (5,10,15,20-[1,4-benzodioxane-6-carboxalde] porphyrin), the in situ assembly is a very convenient and efficient approach for fabricating high-quality ordered patterns. The well-ordered patterns possess strong saturated absorptive and self-defocusing nonlinearities while the TEOP solution exhibit reverse saturated absorption. The value of the nonlinear absorption coefficient of the TEOP ordered pattern and solution differed by three orders of magnitude. (Figure Presented) © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan K.,CAS Beijing National Laboratory for Molecular | Wu D.,CAS Beijing National Laboratory for Molecular | Peng H.,CAS Beijing National Laboratory for Molecular | Jin L.,CAS Dalian Institute of Chemical Physics | And 3 more authors.
Nature Communications | Year: 2012

Device applications of graphene such as ultrafast transistors and photodetectors benefit from the combination of both high-quality p-and n-doped components prepared in a large-scale manner with spatial control and seamless connection. Here we develop a well-controlled chemical vapour deposition process for direct growth of mosaic graphene. Mosaic graphene is produced in large-area monolayers with spatially modulated, stable and uniform doping, and shows considerably high room temperature carrier mobility of ∼5,000 cm 2 V -1 s -1 in intrinsic portion and ∼2,500 cm 2 V -1 s -1 in nitrogen-doped portion. The unchanged crystalline registry during modulation doping indicates the single-crystalline nature of p-n junctions. Efficient hot carrier-assisted photocurrent was generated by laser excitation at the junction under ambient conditions. This study provides a facile avenue for large-scale synthesis of single-crystalline graphene p-n junctions, allowing for batch fabrication and integration of high-efficiency optoelectronic and electronic devices within the atomically thin film. © 2012 Macmillan Publishers Limited. All rights reserved.


Zhang J.,CAS Beijing National Laboratory for Molecular | Maurer F.H.J.,Lund University | Yang M.,CAS Beijing National Laboratory for Molecular
Journal of Physical Chemistry C | Year: 2011

TiO2 nanoparticles were in situ generated in one-dimensional poly(methyl methacrylate) PMMA nanohybrid fibers with excellent dispersion by using electrospinning combined with a sol-gel method followed by a mild hydrothermal treatment that preserves the properties of the polymer to the maximum degree. Detailed information of the preparation method, synthesis route, structure and properties of TiO2/PMMA nanohybrids is revealed. The possible rationale for the uniform formation of TiO2 nanoparticles in the PMMA matrix is discussed with respect to the role of the acid solvent trifluoroacetic acid (TFA) as well as the electrospun fiber structure in the sol-gel and hydrothermal process. The use of TFA in the preparation of electrospun precursor/PMMA solutions induces full hydrolysis of titanium alkoxide. The rapid electrospinning process suppresses the condensation reaction of the precursor. The strong hydrogen bonding interaction between hydrolyzed inorganic precursor and the polymer results in stable precursor/PMMA nanohybrids at ambient conditions. The solid fibrous polymer structure facilitates the generation and homogeneous distribution of nanosized TiO2 particles within the PMMA matrix at hot water conditions, which are ready to be used in biomedical and optical applications. © 2011 American Chemical Society.


Wang H.,CAS Beijing National Laboratory for Molecular | Wu F.,CAS Beijing National Laboratory for Molecular | Jiang H.,CAS Beijing National Laboratory for Molecular
Journal of Physical Chemistry C | Year: 2011

Alkaline tantalates, ATaO3 (A = Li, Na, and K), have attracted a lot of interest in recent years due to their interesting photocatalytic properties and their photocatalytic activity is influenced by a lot of factors, making them ideal model systems for in-depth theoretical investigation. In this work, electronic band structures of alkaline tantalates are investigated based on first-principles many-body perturbation theory in the GW approximation. The band gaps of NaTaO3 and KTaO3 from the GW approach agree very well with experiment; on the other hand, the band gap of LiTaO3 from GW is significantly larger than the experimental values. A strong dependence on crystal structures is observed in LiTaO3, whose band gap in the cubic and rhombohedral structure differs by more than 1.5 eV. Combined with the phenomenological ionic model, it is found that both the Madelung potential and the bandwidth can have strong influences on the band gap. By comparing the structure dependence of LiTaO3 and NaTaO 3, it is concluded that the intra-TaO6-octahedron distortion has stronger effects on electronic band structures than the inter-TaO6-octahedron distortion. Possible causes underlying the discrepancy between GW and experiment for LiTaO3 are also analyzed. © 2011 American Chemical Society.


Zhang M.,CAS Beijing National Laboratory for Molecular | Zhang M.,University of Chinese Academy of Sciences | Guo X.,CAS Beijing National Laboratory for Molecular | Li Y.,CAS Beijing National Laboratory for Molecular
Advanced Energy Materials | Year: 2011

A new D-A copolymer, PDTSTTz, has been synthesized based on a dithienosilole donor unit and a thiazolothiazole acceptor unit for application as a donor material in polymer solar cells (PSCs). The power conversion efficiency of the PSC based on PDTSTTz/PC 70BM (1:1, w/w) with thermal annealing at 100 °C for 15 min reached 5.59% with J SC = 11.9 mA cm -2, V OC = 0.77 V, and FF = 0.61, under the illumination of AM1.5, 100 mW cm -2. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Cao F.-F.,CAS Beijing National Laboratory for Molecular | Guo Y.-.,CAS Beijing National Laboratory for Molecular | Wan L.-J.,CAS Beijing National Laboratory for Molecular
Energy and Environmental Science | Year: 2011

Lithium-ion battery constitutes one of the most popular energy sources which powers current electronic instruments. It is also a promising candidate to be used in future electric devices. To fulfil its potential in future battery market, the better properties of lithium-ion batteries, e.g., higher capacity, better rate performance, are undoubtedly required. The development of nanotechnology has greatly advanced the frontier of lithium-ion battery research. Recently, it was realized that the application of nanocable-like structure in the design of electrodes can significantly improve the properties of lithium-ion batteries. Here we give an overiew of the design, synthesis, and applications of such structures in lithium-ion batteries and highlight some of the latest achievements in this area. It is exciting that the future of lithium-ion batteries is quite bright in view of the high specific capacity, much improved rate performance, as well as superior cycling stability brought by the nanocable-like electrode materials. © The Royal Society of Chemistry 2011.


Sun D.,CAS Beijing National Laboratory for Molecular | Guo H.,CAS Beijing National Laboratory for Molecular
Journal of Physical Chemistry B | Year: 2012

Using Monte Carlo simulation methods, the effects of the comonomer sequence distribution on the interfacial properties (including interfacial tension, interfacial thickness, saturated interfacial area per copolymer, and bending modulus) and interfacial structures (including chain conformations and comonomer distributions of the simulated copolymers at the interfaces) of a ternary symmetric blend containing two immiscible homopolymers and one gradient copolymer are investigated. We find that copolymers with a larger composition gradient width have a broader comonomer distribution along the interface normal, and hence more pronouncedly enlarge the interfacial thickness and reduce the interfacial tension. Furthermore, the counteraction effect, which arises from the tendency of heterogeneous segments in gradient copolymers to phase separate and enter their miscible phases to reduce the local enthalpy, decreases the stretching of copolymers along the interface normal direction. As a result, copolymers with a larger width of gradient composition can occupy a larger interfacial area and form softer monolayers at saturation and are more efficient in facilitating the formation of bicontinuous microemulsions. Additionally, chain length ratio, segregation strength, and interactions between homopolymers and copolymers can alter the interfacial character of gradient copolymers. There exists a strong coupling between the comonomer sequence distribution, chain conformation, and interfacial properties. Especially, bending modulus is mainly determined by the complicated interplay of interfacial copolymer density and interfacial chain conformation. © 2012 American Chemical Society.


Jiang L.,CAS Beijing National Laboratory for Molecular | Jiang L.,University of Chinese Academy of Sciences | Dong H.,CAS Beijing National Laboratory for Molecular | Hu W.,CAS Beijing National Laboratory for Molecular
Soft Matter | Year: 2011

One-dimensional (1D) nanostructures of organic functional materials have attracted extensive attention recently due to their promising applications in high-performance optoelectronic devices. The ability to align and pattern 1D nanostructures into highly ordered arrays and complicated architectures is a prerequisite for integrating them into large-scale functional devices. Recently, enormous efforts have brought significant progress in the development of highly ordered 1D nanostructures of organic functional materials and the fabrication of high performance optoelectronic devices based on these structures. Here, the review will focus on the novel techniques for the fabrication of highly ordered 1D nanostructures and its application for the development of high performance devices and circuits. Finally, the perspectives and opportunities of highly ordered 1D nanostructures in the near future is also addressed. © 2011 The Royal Society of Chemistry.


Nie J.,CAS Beijing National Laboratory for Molecular | Xie J.,CAS Beijing National Laboratory for Molecular | Liu H.,CAS Beijing National Laboratory for Molecular
Journal of Catalysis | Year: 2013

5-Hydroxymethylfurfural (HMF) is an important biomass-based platform chemical, and its selective aerobic oxidation to 2,5-diformylfuran (DFF) remains a formidable challenge. This work reports that activated carbon-supported Ru clusters (Ru/C) efficiently catalyzed HMF oxidation to DFF with a high yield of ∼96% at 383 K and 2.0 MPa O2 in toluene. Ru/C exhibited activities and DFF selectivities superior to those of Ru clusters with similar sizes (ca. 2 nm) on oxide supports, including Al2O3, ZSM-5, TiO2, ZrO2, CeO2, MgO, and Mg 2AlOx, as a consequence of their different surface acidity-basicity and reducibility, which tend to facilitate degradation and polymerization of HMF and DFF. It was also superior to C-supported Pt, Pd, Rh, and Au at comparable sizes in the HMF oxidation to DFF. The effects of O 2 and HMF concentrations on HMF oxidation were examined on Ru/C, showing near half-order dependence of the activities on them. Kinetic isotopic studies showed marked and no kinetic isotopic effects for two HMF molecules deuterated, respectively, at the methylene (kC- H/kC-D = 3.73) and hydroxyl (k O-H/kO-D = 1.09) groups. Taken together, these results are consistent with a Langmuir-Hinshelwood mechanism and a sequence of elementary steps involving kinetically-relevant H-abstraction from adsorbed alcoholate species using adsorbed atomic oxygen species, derived from the quasi-equilibrated dissociation of HMF and O2, respectively, on Ru surfaces. This reaction mechanism leads to a complex kinetic rate expression that accurately describes the measured HMF oxidation activities in a wide range of HMF and O2 concentrations. © 2013 Elsevier Inc. All rights reserved.


Guo P.,CAS Beijing National Laboratory for Molecular | Chen P.,CAS Beijing National Laboratory for Molecular | Chen P.,Zhengzhou University | Liu M.,CAS Beijing National Laboratory for Molecular
ACS Applied Materials and Interfaces | Year: 2013

Surfactant-assisted self-assembly (SAS) has received much attention for supramolecular nanoassemblies, due to its simplicity and easiness in realizing a controllable assembly. However, in most of the existing SAS protocols, the employed surfactants work only as a regulator for a controllable assembly but not as active species for function improvement. In this paper, we report that a porphyrin, zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), could be assembled to form one-dimensional (1D) supramolecular nanostructures via a SAS method, wherein graphene oxide (GO) plays a fascinating role of sheetlike surfactant. We show that, when a chloroform or tetrahydrofuran solution of ZnTPyP is injected into an aqueous dispersion of GO, 1D supramolecular nanoassemblies of ZnTPyP with well-defined internal structures could be easily formulated in a controllable manner. Our experimental facts disclose that the complexation of ZnTPyP with the two-dimensional GO nanosheets plays an important role in this new type of SAS. More interestingly, compared with the 1D ZnTPyP nanoassemblies formulated via a conventional SAS, wherein cetyltrimethylammonium bromide is used as surfactant, those constructed via our GO-assisted SAS display distinctly enhanced photocatalytic activity for the photodegradation of rhodamine B under visible-light irradiation. Our new findings suggest that GO could work not only as an emergent sheetlike surfactant for SAS in terms of supramolecular nanoassembly but also as functional components during the performance of the assembled nanostructures. © 2013 American Chemical Society.


Yan Y.,CAS Beijing National Laboratory for Molecular | Lin Y.,CAS Beijing National Laboratory for Molecular | Qiao Y.,CAS Beijing National Laboratory for Molecular | Huang J.,CAS Beijing National Laboratory for Molecular
Soft Matter | Year: 2011

Self-assembly of small molecules into one-dimensional soft nanostructures offers many advantages in understanding biological process and fabrication of electronically active materials. In recent decades, various one-dimensional soft nanostructures have been fabricated. The present review focuses on the following content: (1) frequently occurring forces in one-dimensional molecular self-assembly; (2) how these forces are used to construct this type of nanostructures; (3) fine-tuning one-dimensional self-assemblies by employing tools such as photo, pH, temperature, additives, and concentration; (4) some examples of the applications of one-dimensional self-assemblies in fabrication of one-dimensional hard materials are described. © 2011 The Royal Society of Chemistry.


Zhang C.,CAS Beijing National Laboratory for Molecular | Zhao Y.S.,CAS Beijing National Laboratory for Molecular | Yao J.,CAS Beijing National Laboratory for Molecular
Physical Chemistry Chemical Physics | Year: 2011

Optical waveguides synthesized at the micro/nanoscale have drawn great interest for their potential applications in high speed miniaturized photonic integrations. In this Perspective article, we mainly focus on the related works on active optical waveguides based on functional small organic molecules in micro/nano regime. We begin with a general overview of recent progress in sub-wavelength optical waveguides, including the development of waveguide materials of inorganic semiconductors, polymers, and small organic molecules. Then brief highlights are put on the recently reported organic optical waveguides with various unique optical properties induced by the ordered molecular aggregations in the micro/nano-sized solid-state structures, such as polarized emission, lasing, aggregation-induced enhanced emission, etc. This article concludes with a summary and our personal view about the direction of future development in organic opto-functional waveguides as photonic devices. © 2011 the Owner Societies.


Yan Y.,CAS Beijing National Laboratory for Molecular | Jiang L.,CAS Beijing National Laboratory for Molecular | Huang J.,CAS Beijing National Laboratory for Molecular
Physical Chemistry Chemical Physics | Year: 2011

CDs may have promising functions in surfactant systems far beyond simply being disadvantageous to the formation of micelles. In this paper we review the recent literature and our work on the interesting effect of CDs on amphiphilic systems, especially on the concentrated single surfactant systems and catanionic surfactant mixed systems, both of them have been scarcely focused upon in the literature. In concentrated single surfactant systems, the 2:1 surfactant-CD inclusion complexes may form hierarchical self-assemblies such as lamellae, microtubes, and vesicles which are driven by hydrogen bonding. In nonstoichiometrically mixed catanionic surfactant systems, CDs behave as a stoichiometry booster that always selectively binds to the excess component so as to shift the mixing ratio to electro-neutral in the aggregates. In this way, CDs reduce the electrorepulsion in the aggregates and trigger their growth. Upon analysis of literature work and our own results, we expect that a new era focusing on the new function of CDs on surfactant systems will come. © 2011 the Owner Societies.


Su J.,CAS Beijing National Laboratory for Molecular | Guo H.,CAS Beijing National Laboratory for Molecular
Journal of Physical Chemistry B | Year: 2012

From the perspectives of biological applications and material sciences, it is essential to understand the transport properties of water molecules through nanochannels. Although considerable effort and progress has been made in recent years, a systematic understanding of the effect of nanochannel dimension is still lacking. In this paper, we use molecular dynamics (MD) simulations to study the transport of water molecules through carbon nanotubes (CNTs) with various dimensions under pressure differences. We find an exponential decay describing the relation of the water flow and CNT lengths (L) for different pressures. The average translocation time of individual water molecules yields to a power law relation with L. We also exploit these results by comparing with the single-file transport, where some interesting relations were figured. Meanwhile, for a given CNT length, the water flow vs CNT diameters (R) can be depicted by a power law, which is found to be relevant to the water occupancy inside the nanochannel. In addition, we compare our MD results with predictions from the no-slip Hagen-Poisseuille (HP) relation. The dependence of the enhancement of the simulated water flux over the HP prediction on the CNT length and diameter supports previous MD and experimental studies. Actually, the effect of nanotube dimension is not only originated from the motion of water molecules inside the CNT but also related to thermal fluctuations in the bulk water outside the CNT. These results enrich our knowledge about the channel size effect on the water transportation, which should have deep implications for the design of nanofluidic devices. © 2012 American Chemical Society.


Shi W.,CAS Beijing National Laboratory for Molecular | Sun S.,CAS Beijing National Laboratory for Molecular | Li X.,CAS Beijing National Laboratory for Molecular | Ma H.,CAS Beijing National Laboratory for Molecular
Inorganic Chemistry | Year: 2010

Rhodamine B selenolactone has been designed, synthesized, and characterized as a new fluorescent probe for imaging both Hg2+ and Ag+ in live cells to better understand their distinct toxicities to organisms. The probe is designed based on the fact that selenium has a strong affinity for mercury and silver, and is constructed by incorporating a Se atom into the spirocyclic structure of rhodamine. It exhibits a rapid and specific spectroscopic off-on response to Hg2+ and Ag+ instead of other species, with detection limits of 23 nM Hg2+ and 52 nM Ag +. Moreover, the probe is membrane-permeable, and can react with Ag+ even in the presence of Cl- because of the higher affinity of Se than Cl- for Ag+, which makes it of potential use for imaging not only Hg2+ but also Ag+ in live cells. This applicability has been demonstrated by imaging Hg2+ and Ag+ in Hela cells. It is observed that the reaction of Ag + with the probe inside the cells occurs much slower than that of Hg2+, which is ascribed to the high concentration of cellular chloride ions inhibiting the formation of sufficient free Ag+. The present finding is helpful to get an insight into the different interaction mechanism of Hg2+ and Ag+ with cells, and more applications of the probe may be expected for studying the behaviors of Hg 2+ and Ag+ in various biosystems. © 2009 American Chemical Society.


Ye X.,CAS Beijing National Laboratory for Molecular | Qi L.,CAS Beijing National Laboratory for Molecular
Science China Chemistry | Year: 2014

Monolayer colloidal crystals (MCCs) are two-dimensional (2D) colloidal crystals consisting of a monolayer of monodisperse colloidal particles arrayed with a 2D periodic order. In recent years, MCCs have attracted intensive interest because they can act as 2D photonic crystals and be used as versatile templates for fabrication of various 2D nanostructure arrays. In this review, we provide an overview of the recent progress in the controllable fabrication of MCCs and their inverse replicas. First, some newly-developed methods for the self-assembly of MCCs based on different strategies including interfacial assembly and convective assembly are introduced. Second, some representative novel methods regarding the fabrication of various functional 2D inverse replicas of MCCs, such as 2D arrays of nanobowls, nanocaps, and hollow spheres, as well as 2D monolayer inverse opals (MIOs), are described. In addition, the potential applications of MCCs and their inverse replicas are discussed. © 2013 Science China Press and Springer-Verlag Berlin Heidelberg.


Ye J.,CAS Beijing National Laboratory for Molecular | Liu W.,CAS Beijing National Laboratory for Molecular | Cai J.,CAS Beijing National Laboratory for Molecular | Chen S.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Journal of the American Chemical Society | Year: 2011

Unique spindle-shaped nanoporous anatase TiO2 mesocrystals with a single-crystal-like structure and tunable sizes were successfully fabricated on a large scale through mesoscale assembly in the tetrabutyl titanate-acetic acid system without any additives under solvothermal conditions. A complex mesoscale assembly process involving slow release of soluble species from metastable solid precursors for the continuous formation of nascent anatase nanocrystals, oriented aggregation of tiny anatase nanocrystals, and entrapment of in situ produced butyl acetate as a porogen was put forward for the formation of the anatase mesocrystals. It was revealed that the acetic acid molecules played multiple key roles during the nonhydrolytic processing of the [001]-oriented, singlecrystal-like anatase mesocrystals. The obtained nanoporous anatase mesocrystals exhibited remarkable crystalline-phase stability (i.e., the pure phase of anatase can be retained after being annealed at 900 °C) and improved performance as anode materials for lithium ion batteries, which could be largely attributed to the intrinsic single-crystal-like nature as well as high porosity of the nanoporous mesocrystals. © 2010 American Chemical Society.


Wang Y.,CAS Beijing National Laboratory for Molecular | Du H.,CAS Beijing National Laboratory for Molecular
Journal of Organic Chemistry | Year: 2010

This paper describes a copper(II) acetate-mediated cyclization- acetoxylation of 6,8-dien-1-ones in the presence of sodium acetate as base. A variety of functionalized cyclopentanes containing synthetic useful allylic alcohol moieties with three contiguous stereogenic centers were synthesized in moderate to good yields with moderate to high regioselectivities. © 2010 American Chemical Society.


Duan X.,CAS Beijing National Laboratory for Molecular | Liu L.,CAS Beijing National Laboratory for Molecular | Feng F.,CAS Beijing National Laboratory for Molecular | Wang S.,CAS Beijing National Laboratory for Molecular
Accounts of Chemical Research | Year: 2010

(Figure Presented) Simple, rapid, and sensitive technologies to detect nucleic acid modifications have important applications in genetic analysis, clinical diagnosis, and molecular biology. Because genetic modifications such as single nucleotide polymorphisms (SNP), DNA methylation, and other lesions can serve as hallmarks of human disease, interest in such methods has increased in recent years. This Account describes a new strategy for the optical detection of these DNA targets using cationic conjugated polymers (CCPs). Because of their unique signal amplification properties, researchers have extensively investigated conjugated polymers as optical transducers in highly sensitive biosensors. Recently, we have shown that cationic polyfluorene can detect SNPs within the DNA of clinical samples. When we incorporated deoxyguanosine triphosphate (dGTP-FI) into the DNA chain at an SNP site where the target/probe pair is complementary, we observed higher fluorescence resonance energy transfer (FRET) efficiency between cationic polyfluorene and fluorescein label on the dGTP. By monitoring the change in emission intensity of cationic polyfluorene or fluorescein, we identified the homozygous or heterozygous SNP. The high sensitivity of this assay results from the 10-fold enhancement of fluorescein emission intensity by the FRET from polyfluorene. This method can detect allele frequencies (the proportion of all copies of a gene that is made up of a particular gene variant) as low as 2%. Using this novel method, we clearly discriminated among the SNP genotypes of 76 individuals of Chinese ancestry. Improving on this initial system, we designed a method for multicolor and one-tube SNP genotyping assays based on cationic polyfluorene using fluorescein-labeled deoxyuridine triphosphate (dUTP-FI) and Cy3-labeled deoxycytidine triphosphate (dCTPCy3) in extension reactions. We also developed a one-step method for direct detection of SNP genotypes from genomic DNA by combining allele-specific PCR with CCPs. In 2008, we developed a new method for DNA methylation detection based on single base extension reaction and CCPs. Treatment of DNA with bisulfite followed by PCR amplification converts unmethylated DNA into a C/T polymorphism, which allows us to characterize the methylation status of the target DNA. Furthermore, we used CCPs to detect DNA lesions caused by ultraviolet light irradiation for the first time. By monitoring the color change of cationic polythiophene before and after DNA cleavage, we also detected oxidative damage to DNA by hydroxyl radical. These CCP-based new assays avoid primer labeling, cumbersome workups, and sophisticated instruments, leading to simpler procedures and improved sensitivity. We expect that these features could lead to major advances in human disease diagnostics and genomic study in the near future. © 2010 American Chemical Society.


Cao C.-Y.,CAS Beijing National Laboratory for Molecular | Qu J.,CAS Beijing National Laboratory for Molecular | Yan W.-S.,Hefei University of Technology | Zhu J.-F.,Hefei University of Technology | And 2 more authors.
Langmuir | Year: 2012

Flowerlike α-Fe 2O 3 nanostructures were synthesized via a template-free microwave-assisted solvothermal method. All chemicals used were low-cost compounds and environmentally benign. These flowerlike α-Fe 2O 3 nanostructures had high surface area and abundant hydroxyl on their surface. When tested as an adsorbent for arsenic and chromium removal, the flowerlike α-Fe 2O 3 nanostructures showed excellent adsorption properties. The adsorption mechanism for As V and Cr VI onto flowerlike α-Fe 2O 3 nanostructures was elucidated by X-ray photoelectron spectroscopy and synchrotron-based X-ray absorption near edge structure analysis. The results suggested that ion exchange between surface hydroxyl groups and As V or Cr VI species was accounted for by the adsorption. With maximum capacities of 51 and 30 mg g -1 for As V and Cr VI, respectively, these low-cost flowerlike α-Fe 2O 3 nanostructures are an attractive adsorbent for the removal of As V and Cr VI from water. © 2012 American Chemical Society.


Zhu M.,CAS Beijing National Laboratory for Molecular | Chen P.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular
Langmuir | Year: 2012

In this article, we report that Ag/AgBr nanostructures and the corresponding graphene oxide (GO) hybridized nanocomposite, Ag/AgBr/GO, could be facilely synthesized by means of a surfactant-assisted assembly protocol, where an oil/water microemulsion is used as the synthesis medium. We show that thus-produced nanomaterials could be used as highly efficient and stable plasmonic photocatalysts for the photodegradation of methyl orange (MO) pollutant under sunlight irradiation. Compared with the bare Ag/AgBr nanospecies, Ag/AgBr/GO displays distinctly enhanced photocatalytic activity. More importantly, the as-prepared nanostructures exhibit higher photocatalytic activity than that of the corresponding Ag/AgBr-based nanomaterials synthesized via a water/oil microemulsion and than that of the corresponding Ag/AgCl-based nanospecies synthesized by an oil/water microemulsion. An explanation has been proposed for these interesting findings. Our results suggest that thus-manufactured Ag/AgBr/GO plasmonic photocatalysts are promising alternatives to the traditional UV light or visible-light driven photocatalysts. © 2012 American Chemical Society.


Zheng J.,CAS Beijing National Laboratory for Molecular | Zhang H.,CAS Beijing National Laboratory for Molecular | Zhao Z.,CAS Beijing National Laboratory for Molecular | Han C.C.,CAS Beijing National Laboratory for Molecular
Polymer | Year: 2012

To expand the application of electrospun fibers or electrosprayed beads, micro-nano hierarchical structures of polystyrene (PS) have been constructed through the adjustment of solvent, polymer concentration, environment humidity, electrospinning temperature, etc. Primary structures, such as fibers, beads and bead-on-string structure, as well as secondary structures, such as nanopores, nanopapilla and net-work structure, have been constructed. Solvent plays an important role in the construction of both primary structures and secondary structures. By using N,N-dimethylformamide (DMF), tetrahydrofuran (THF) and mixed solvent of DMF/THF, the micro-nano hierarchical structures can be controlled. Humidity is a key factor to the construction of secondary structures. The obtained fibers or beads have smooth surface at low humidity. While at high humidity, secondary structures tend to appear. For the PS/DMF system, vapor-induced phase separation may be the most pertinent mechanism to explain the formation of secondary structures. While for the PS/THF system, breath figure theory can explain the formation of uniform nanopores properly. © 2011 Elsevier Ltd. All rights reserved.


Yang G.,CAS Beijing National Laboratory for Molecular | Liu L.,CAS Beijing National Laboratory for Molecular | Yang Q.,CAS Beijing National Laboratory for Molecular | Lv F.,CAS Beijing National Laboratory for Molecular | Wang S.,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2012

At present, there is an urgent necessity for the discovery of new chemotherapeutic agents with novel molecular skeleton structures that exhibit wide spectrum antitumor activity. In this work, a cationic pentathiophene (5T) is synthesized and discovered to have both anticancer activity and molecular imaging property. 5T can selectively accumulate in mitochondria to exhibit organellar imaging and efficiently induce cell apoptosis associating with JNK pathway activation. Additionally, complexes are prepared through electrostatic interactions between 5T and sodium chlorambucil (a widely used anticancer drug) with varying molar ratios. The complexes form nanoparticles in water with the size of about 50 nm. The 5T-chlorambucil nanoparticles enhance anticancer activity by 2-9 fold due to the synergistical anticancer activity of 5T and chlorambucil. 5T is therefore a promising multifunctional anticancer agent that incorporates optical monitoring capability and anticancer activity that targets mitochondria. A cationic pentathiophene (5T) is synthesized and discovered with both anticancer activity and molecular imaging properties. 5T can selectively accumulate in mitochondria to exhibit organellar imaging and efficiently induce cell apoptosis associating with c-jun N-terminal kinase (JNK) JNK pathway activation. The 5T-chlorambucil nanoparticles enhance anticancer activity by 2 to 9 fold due to the synergistical anticancer activity of 5T and chlorambucil. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Yan Y.,CAS Beijing National Laboratory for Molecular | Zhao Y.S.,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2012

Nanophotonic circuits meet exciton polaritons (EPs) in organic nanomaterials: Great possibilities for the use of organic 1D crystalline nanostructures as building blocks are emerging. These remarkable studies will contribute significantly to the development of EP-based on-chip photonic devices in the near future. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu X.,CAS Beijing National Laboratory for Molecular | Wang T.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular
Langmuir | Year: 2012

A series of bolaamphiphiles with 4-hydroxycinnamoyl head groups and different length of the alkyl spacers (n = 6-12) were designed to investigate their photochemistry in the organized films obtained from the air/water interface. It has been found that both the length and odd-even number of the spacers can finely tune the molecular packing as well as the photochemistry. When the spacer length was changed from 6 to 12 methylene units, the assemblies changed from J aggregate to H aggregate. The molecules with evennumbered polymethylene spacer tend to form three-dimensional nanorod structure at the air/water interface. For the assembly of derivatives with odd-numbered spacers, diverse morphologies such as nanospirals and nanofibers were observed depending on the chain length and the surface pressures. The different packing of bolaamphiphiles could subsequently affect the photochemistry of the cinnamoyl groups in the organized films. The spacer effect in the assembly can be understood from the cooperation between Hbond of the phenolic hydroxyl and the amide groups, ?-? stacking as well as the hydrophobic interactions of the alkyl spacer. A packing model was proposed to explain the phenomenon. © 2012 American Chemical Society.


Yi Z.,Huazhong University of Science and Technology | Wang S.,Huazhong University of Science and Technology | Liu Y.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2015

Since the report of the first diketopyrrolopyrrole (DPP)-based polymer semiconductor, such polymers have received considerable attention as a promising candidate for high-performance polymer semiconductors in organic thin-film transistors (OTFTs). This Progress Report summarizes the advances in the molecular design of high-mobility DPP-based polymers reported in the last few years, especially focusing on the molecular design of these polymers in respect of tuning the backbone and side chains, and discussing the influences of structural modification of the backbone and side chains on the properties and device performance of corresponding DPP-based polymers. This provides insights for the development of new and high-mobility polymer semiconductors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhang Q.,CAS Beijing National Laboratory for Molecular | Zhang Q.,University of Chinese Academy of Sciences | Sun Y.,CAS Beijing National Laboratory for Molecular | Xu W.,CAS Beijing National Laboratory for Molecular | Zhu D.,CAS Beijing National Laboratory for Molecular
Advanced Materials | Year: 2014

The abundance of solar thermal energy and the widespread demands for waste heat recovery make thermoelectric generators (TEGs) very attractive in harvesting low-cost energy resources. Meanwhile, thermoelectric refrigeration is promising for local cooling and niche applications. In this context there is currently a growing interest in developing organic thermoelectric materials which are flexible, cost-effective, eco-friendly and potentially energy-efficient. In particular, the past several years have witnessed remarkable progress in organic thermoelectric materials and devices. In this review, thermoelectric properties of conducting polymers and small molecules are summarized, with recent progresses in materials, measurements and devices highlighted. Prospects and suggestions for future research efforts are also presented. The organic thermoelectric materials are emerging candidates for green energy conversion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Hu R.,CAS Beijing National Laboratory for Molecular | Feng J.,CAS Beijing National Laboratory for Molecular | Hu D.,CAS Beijing National Laboratory for Molecular | Wang S.,CAS Beijing National Laboratory for Molecular | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2010

(Figure Presented) The color purple: A siloxy-functionalized benzamide (see picture) is a highly efficient fluoride ion sensor in water. The sensor, which is activated when the O-Si bond is cleaved by fluoride ions, provides two independent modes for signal recognition. In colorimetric mode, the fluoride ion concentration is transformed into a fluorescence signal that can be observed directly with the naked eye. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, weinheim.


Lang X.,Nanyang Technological University | Zhao J.,CAS Beijing National Laboratory for Molecular | Chen X.,Nanyang Technological University
Chemical Society Reviews | Year: 2016

Visible-light photoredox catalysis has been experiencing a renaissance in response to topical interest in renewable energy and green chemistry. The latest progress in this area indicates that cooperation between photoredox catalysis and other domains of catalysis could provide effective results. Thus, we advance the concept of cooperative photoredox catalysis for organic transformations. It is important to note that this concept can bridge the gap between visible-light photoredox catalysis and other types of redox catalysis such as transition-metal catalysis, biocatalysis or electrocatalysis. In doing so, one can take advantage of the best of both worlds in establishing organic synthesis with visible-light-induced redox reaction as a crucial step. © 2016 The Royal Society of Chemistry.


Kong D.,Stanford University | Dang W.,CAS Beijing National Laboratory for Molecular | Cha J.J.,Stanford University | Li H.,CAS Beijing National Laboratory for Molecular | And 4 more authors.
Nano Letters | Year: 2010

A topological insulator (TI) represents an unconventional quantum phase of matter with insulating bulk band gap and metallic surface states. Recent theoretical calculations and photoemission spectroscopy measurements show that group V-VI materials Bi2Se3, Bi2Te3, and Sb2Te3 are TIs with a single Dirac cone on the surface. These materials have anisotropic, layered structures, in which five atomic layers are covalently bonded to form a quintuple layer, and quintuple layers interact weakly through van der Waals interaction to form the crystal. A few quintuple layers of these materials are predicted to exhibit interesting surface properties. Different from our previous nanoribbon study, here we report the synthesis and characterizations of ultrathin Bi2Te3 and Bi2Se3 nanoplates with thickness down to 3 nm (3 quintuple layers), via catalyst-free vapor-solid (VS) growth mechanism. Optical images reveal thickness-dependent color and contrast for nanoplates grown on oxidized silicon (300 nm SiO2/Si). As a new member of TI nanomaterials, ultrathin TI nanoplates have an extremely large surface-to-volume ratio and can be electrically gated more effectively than the bulk form, potentially enhancing surface state effects in transport measurements. Low-temperature transport measurements of a single nanoplate device, with a high-k dielectric top gate, show decrease in carrier concentration by several times and large tuning of chemical potential. © 2010 American Chemical Society.


Chen X.,CAS Beijing National Laboratory for Molecular | Chen X.,University of Chinese Academy of Sciences | Wu B.,CAS Beijing National Laboratory for Molecular | Liu Y.,CAS Beijing National Laboratory for Molecular
Chemical Society Reviews | Year: 2016

Graphene, an amazing two-dimensional material with excellent physical properties, has attracted great attention in various disciplines. Both fundamental studies and applications require graphene samples with controlled parameters including their quality, size, crystallinity, layer number and so on. While graphene can be prepared by direct exfoliation from mother materials or growth on transition metals, the uncontrolled production or the additional complex transfer process has been challenging for graphene applications. Direct preparation on a desired dielectric substrate is an important research direction that potentially addresses these problems. Many advances have been made in the past few years, and this tutorial review provides a brief summary of ways of preparing graphene on dielectric substrates. Various methods including the annealing method, direct chemical vapor deposition graphene synthesis on conventional dielectric substrates and hexagonal boron nitride layers are systematically reviewed and discussed. The main problems and further directions in this field are also presented. © The Royal Society of Chemistry 2016.


Dang W.,CAS Beijing National Laboratory for Molecular | Peng H.,CAS Beijing National Laboratory for Molecular | Li H.,CAS Beijing National Laboratory for Molecular | Wang P.,CAS Beijing National Laboratory for Molecular | Liu Z.,CAS Beijing National Laboratory for Molecular
Nano Letters | Year: 2010

The authors present a van der Waals epitaxy of high-quality ultrathin nanoplates of topological insulator Bi2Se3 on a pristine graphene substrate using a simple vapor-phase deposition method. Sub-10-nm-thick nanoplates of layered Bi2Se3 with defined orientations can be epitaxially grown on a few-layer pristine graphene substrate. We show the evolution of Raman spectra with the number of Bi2Se3 layers on few-layer graphene. Bi2Se3 nanoplates with a thickness of three quintuple-layers (3-QL) exhibit the strongest Raman intensity. Strain effects in the Bi2Se3/graphene nanoplate heterostructures is also studied by Raman spectroscopy. 1-QL and 2-QL Bi 2Se3 nanoplates experience tensile stress, consistent with compressive stress in single-layer and bilayer graphene substrates. Our results suggest an approach for the synthesis of epitaxial heterostructures that consist of an ultrathin topological insulator and graphene, which may be a new direction for electronic and spintronic applications. © 2010 American Chemical Society.


Jia Y.,CAS Beijing National Laboratory for Molecular | Li J.,CAS Beijing National Laboratory for Molecular
Chemical Reviews | Year: 2015

Researchers specifically provide information about covalent molecular assembly with the layer-by-layer (LbL) method through Schiff base interactions, including properties and advantages of Schiff base interactions, the micro- and nanostructures fabricated through Schiff base interactions, and the biomedical applications of the products fabricated through Schiff base interactions. Schiff base interactions are preferred as in situ Schiff base formation avoids the extra post-treatment processes to improve the stability of the multilayer and Schiff base reactions can be conducted both in aqueous and in organic solutions. This allows for incorporating materials that only dissolve or only can be used in nonaqueous solutions.


Shen Y.,CAS Beijing National Laboratory for Molecular | Fu X.,CAS Beijing National Laboratory for Molecular | Fu W.,CAS Beijing National Laboratory for Molecular | Li Z.,Qingdao University of Science and Technology
Chemical Society Reviews | Year: 2015

The stimuli-responsive polypeptides have drawn extensive attention because of their promising applications in biotechnology considering their biocompatibility, biodegradability, and bioactivity. In this tutorial review, we summarize the most recent progress in this area, including thermo-, redox-, photo-, and biomolecule responsive polypeptides over the past decade. The design and synthesis of stimuli-responsive polypeptides will be briefly introduced. The correlation between the structure and properties, particularly the effects of polypeptide conformation, will be emphasized here. In addition, the applications of stimuli-responsive polypeptides in controlled drug release and tissue engineering are briefly discussed. © The Royal Society of Chemistry 2015.


Yan N.,Ecole Polytechnique Federale de Lausanne | Yuan,Ecole Polytechnique Federale de Lausanne | Dykeman R.,Ecole Polytechnique Federale de Lausanne | Kou Y.,CAS Beijing National Laboratory for Molecular | Dyson P.J.,Ecole Polytechnique Federale de Lausanne
Angewandte Chemie - International Edition | Year: 2010

Oxy-gone in a tandem: A catalytic system composed of metal nanoparticles (NPs) and a functionalized Brensted acidic ionic liquid (IL), both of which are immobilized in a nonfunctionalized IL, is highly efficient in upgrading lignin-derived phenolic compounds into alkanes; the hydrogenation and dehydration reactions take place in tandem. Figure Presented © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li J.,CAS Beijing National Laboratory for Molecular | Yu Y.,CAS Beijing National Laboratory for Molecular | Chen Q.,CAS Beijing National Laboratory for Molecular | Xu D.,CAS Beijing National Laboratory for Molecular
Crystal Growth and Design | Year: 2010

A novel type of titanium precursor, ammonium-exchanged titanate nanowires, is used to hydrothermally synthesize nanosized TiO2 single crystals with well-defined facets. With additives of appropriate shape-capping reagents, octahedral, truncated octahedral, and spindle-like TiO2 nanocrystals have been obtained. We proposed that the transformation mechanism from ammonium-exchanged titanate nanowires to TiO2 may be a "dissolution-nucleation" process. Furthermore, the photocatalytic activities of anatase TiO2 nanocrystals with different facets exposed have been investigated. © 2010 American Chemical Society.


Hong G.,CAS Beijing National Laboratory for Molecular | Li C.,CAS Beijing National Laboratory for Molecular | Limin Qi,CAS Beijing National Laboratory for Molecular
Advanced Functional Materials | Year: 2010

Large-area, freestanding, two-dimensionally ordered macroporous (2DOM) Ag thin films with adjustable periodic spacings and good mechanical robustness were fabricated via nanosphere lithography at the solution surface (NSLSS) combined with interfacial reactions. The obtained 2DOM Ag thin films exhibited typical properties of plasmonic crystals with well-resolved reflectivity dips and vivid colors. The facile NSLSS method enabled the 2DOM Ag thin films to be readily transferred to arbitrary substrates to realize application as thin film sensors. Their application as both a surface plasmon resonance (SPR) sensor and a surface-enhanced Raman scattering (SERS) sensor in the detection of both small molecules and biological macromolecules were explored. As SERS substrates for the detection of 4-aminothiophenol (4-ATP) molecules, the 2DOM Ag thin films showed enhancement factors as high as the 107 order, which made them a promising sensor for the detection of trace amount of analyte adsorbed on the surface. As SPR sensors, the 2DOM Ag thin films modified with a self-assembled monolayer of recognizing molecules as binding sites showed remarkable shift in the reflectivity dips responsive to the chemical environments. When used for the specific detection of avidin molecules, the 2DOM Ag thin film biosensors exhibited excellent performance with low detection limit (≈100 pM) and broad working range (100 pM200 nM), indicating that they may be a promising candidate for high-performance biosensors. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Liu Y.,CAS Beijing National Laboratory for Molecular | Chen P.,CAS Beijing National Laboratory for Molecular | Li Z.,CAS Beijing National Laboratory for Molecular
Macromolecular Rapid Communications | Year: 2012

A new type of molecular bottlebrush with poly-L-lysine (PLL) as backbone was synthesized via ROP followed by ATRP. A Nε-bromoisobutyryl functionalized Nα-CBZ-L-lysine was firstly synthesized and converted in polymerizable α-amino acid N-carboxyanhydride (NCA), which was then polymerized using Ni(0) transition metal complex to give well-defined bromo-functionalized homopolypeptide (PBrLL), from which we prepared two types of polypeptide bottlebrushes with polystyrene and poly(oligoethylene glycol methacrylate) as side-chains. PBrLL macroinitiator was demonstrated to have high initiation efficiency for ATRP, which allowed good control over side-chain length. CD and FTIR characterization revealed that both PBrLL macroinitiator and PLL backbone of bottlebrushes adopted α-helical conformation in appropriate solvents. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Man X.,CAS Beijing National Laboratory for Molecular | Yan D.,CAS Beijing National Laboratory for Molecular
Macromolecules | Year: 2010

Self-consistent-field theory (SCFT) is presented to study the charge inversion phenomena by flexible polyelectrolytes (PE) adsorbed onto oppositely charged cylindric surfaces. We focus on the effect of surface curvature on the charge inversion ratio between the area density of surface charge compensated by the adsorbed polymers and the area density of origin surface charge. Numerical results show that surface curvature does have a strong effect on the charge inversion phenomena. Namely, it can lead to strong charge inversion at high salt concentrations with strong surface-PE short-range non-Coulombic interaction even in a good solvent. In particular, under large surface curvature and strong short-range non-Coulombic interaction conditions, full charge inversion can even happen at low salt concentrations. Moreover, numerical results show that the surface curvature has a different effect on the charge inversion ratio in the regime dominated by the surface-PE electrostatic interaction and in the regime dominated by the surface-PE shortrange non-Coulombic interaction. Increasing surface curvature will decrease the charge inversion ratio in the former case, while it will increase it in the latter case. Also, we numerically obtain a crossover point for the cylinder radius, which approximately equates to 2 times the gyration radius of PE chain. When the cylinder radius becomes larger than it, the surface curvature will lose its effect on the charge inversion. The numerical results give a further demonstration that, in these weakly charged systems, the surface-PE short-range nonCoulombic interaction is the main driving force of charge inversion phenomena. The results are in good agreement with the theoretical and experimental results. © 2010 American Chemical Society.


Tao M.,Ningbo Institute of Materials Technology and Engineering | Xue L.,Ningbo Institute of Materials Technology and Engineering | Liu