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Wang C.,Key Laboratory of Applied Surface and Colloid Chemistry
Chemical Record | Year: 2016

This article provides an account of our group's efforts in developing aqueous-phase transfer hydrogenation reactions. It is comprised of mainly two parts. The first part concentrates on asymmetric transfer hydrogenation in water, enabled by Noyori-Ikariya catalysts, while the second part is concerned with the achiral version of the reaction catalysed by a new class of catalysts, iridacycles. A range of substrates are featured, including various carbonyl compounds and N-heterocycles. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.


Li Y.,Xi'an Modern Chemistry Research Institute | Tu D.-H.,Xi'an Modern Chemistry Research Institute | Gu Y.-J.,Xi'an Modern Chemistry Research Institute | Wang B.,Xi'an Modern Chemistry Research Institute | And 3 more authors.
European Journal of Organic Chemistry | Year: 2015

The palladium-catalyzed oxidative Heck reaction of 2,3,3,3-tetrafluoroprop-1-ene with various arylboronic acids was explored for the first time. This method provides a direct route to access (Z)-β-fluoro-β-(trifluoromethyl)styrenes with high stereoselectivity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zhao B.-H.,Key Laboratory of Applied Surface and Colloid Chemistry | Zhao B.-H.,Shaanxi Normal University | Chen J.-G.,Key Laboratory of Applied Surface and Colloid Chemistry | Chen J.-G.,Shaanxi Normal University | And 10 more authors.
Industrial and Engineering Chemistry Research | Year: 2012

Pt/MWCNT and Pd/MWCNT nanocatalysts were prepared via a liquid reduction method. The selective hydrogenation of cinnamaldehyde (CAL) was investigated over 5.0 wt.% Pt/MWCNT and 5.0 wt.% Pd/MWCNT catalysts in a CO 2-expanded alcoholic medium at different reaction conditions. The hydrogenation selectivities over these two catalyst types were shown to be entirely different. It was found that the Pt/MWCNT catalysts are highly selective for C-O bonds, giving the unsaturated alcohol a selectivity for cinnamyl alcohol (COL) of 97.3% and a conversion rate for cinnamaldehyde of 99.3%. Conversely, the Pd/MWCNT catalyst is highly selective for C-C bonds, producing a saturated aldehyde with a selectivity for hydrocinnamaldehyde (HCAL) of 91.3% and a conversion rate for cinnamaldehyde of 98.6%. The small diameter of the Pt or Pd granules over the multiwalled carbon nanotubes (MWCNTs) leads to a high catalyst activity, and an increase of CO 2 pressure results in a better hydrogenation performance for C-O bonds than that for C-C bonds. © 2012 American Chemical Society.


Qin W.,CAS Dalian Institute of Chemical Physics | Qin W.,University of Chinese Academy of Sciences | Yu W.,CAS Dalian Institute of Chemical Physics | Yu W.,University of Chinese Academy of Sciences | And 13 more authors.
Journal of Materials Chemistry A | Year: 2014

Organic/amorphous silicon (a-Si) hybrid tandem solar cells have the potential to provide a highly efficient low-cost photovoltaic technology using abundant elements, and the technology is adaptable to large-scale processes. With their high open-circuit voltage (Voc) and adaptability to a broad solar spectrum, organic/a-Si tandem devices offer significantly improved performance. We have shown that organic/a-Si hybrid tandem solar cells with a complementary organic absorber can exhibit a power conversion efficiency (PCE) of up to 7.5%, with a fill factor (FF) of 72.3% and a Voc almost equivalent to the sum of the sub-cells under standard air mass (AM) 1.5 illumination. The high performance of the device results from the complementary absorption spectra of two sub-cells and well-matched energy levels of the intermediate layer. This study provides an effective design strategy for organic/a-Si hybrid tandem solar cells of improved efficiency. © the Partner Organisations 2014.


Guo J.,Key Laboratory of Applied Surface and Colloid Chemistry | Yu B.,Key Laboratory of Applied Surface and Colloid Chemistry | Wang Y.-N.,Key Laboratory of Applied Surface and Colloid Chemistry | Duan D.,Key Laboratory of Applied Surface and Colloid Chemistry | And 3 more authors.
Organic Letters | Year: 2014

A Lewis acid promoted cascade cycloaddition/ring-opening of 2-furylcarbinols with alkyl or aryl azides is described. The reaction features an initial formal [3 + 2] cycloaddition to form a trisubstitued triazole motif, followed by a ring opening of furan to generate the (E)-configuration of the enone. A wide range of highly functionalized triazoles is expediently and efficiently synthesized in a highly step-economical manner. © 2014 American Chemical Society.


Liu L.,Key Laboratory of Applied Surface and Colloid Chemistry | Gao M.-N.,Key Laboratory of Applied Surface and Colloid Chemistry | Li Y.,Key Laboratory of Applied Surface and Colloid Chemistry | Li Z.,Key Laboratory of Applied Surface and Colloid Chemistry | And 7 more authors.
Current Organic Chemistry | Year: 2013

A new proline derivative of (S)-5-prolylamide-triazole was synthesized and evaluated as an organocatalyst for the direct asymmetric aldol reaction of acetone with aromatic aldehydes under no extra solvent. At room temperature and in the absence of extra solvent, 15 mol% catalyst efficiently catalyzed the direct asymmetric aldol reactions to give aldol adducts, with modest enantiomeric excess (ee) of up to 74%. The titled reactions can be carried out in an environmentally friendly manner of no extra solvent and less catalyst loading. © 2013 Bentham Science Publishers.


Zhao W.,Key Laboratory of Applied Surface and Colloid Chemistry | Zhao W.,Ningxia Teachers University | Ma Q.,Key Laboratory of Applied Surface and Colloid Chemistry | Li L.,Key Laboratory of Applied Surface and Colloid Chemistry | And 2 more authors.
Journal of Adhesion Science and Technology | Year: 2014

Surface roughness of acrylonitrile-butadiene-styrene (ABS) resin prior to metallization is treated generally with sulphuric/chromic acid system. However, the presence of chrominum (VI) ion imposes serious environmental problems. In this work, TiO2 photocatalytic treatment was used to enhance the adhesion strength between the ABS surface and the electroless copper film. Effects of the TiO2 content, irradiation time and UV power upon the surface topography, surface characterization and the adhesion strength were investigated. The results indicated that the surface hydrophilicity of ABS resin and the adhesion strength between the electroless copper film and ABS surface increased with an increase in the UV power and a prolongation in irradiation time, and did not increase linearly with an increase of TiO2 content. Though the surface topography of ABS changed little, the adhesion strength reached 1.25 kN/m, which was higher than that in the optimal H 2SO4-MnO2colloid. The surface chemistry results indicated that -COOH and -OH groups formed with the photocatalytic treatment and the absorption strengths increased with the UV power. XPS analysis results further demonstrated that the contents of C=O and -COOH reached 6.4 and 4.9% with the photocatalytic treatment, which was much higher than that of the H 2SO4-MnO2 colloid (3.9 and 3.1%). The high contents of C=O and -COOH groups enhanced the surface hydrophilicity of the ABS resin and improved the adhesion strength between the electroless copper film and ABS resin. The results indicated that the photocatalytic treatment was an environment-friendly and effective method to replace the commercial wet chemical process for ABS surface modification. © 2013 Taylor & Francis.


Zi W.,Key Laboratory of Applied Surface and Colloid Chemistry | Ren X.,Key Laboratory of Applied Surface and Colloid Chemistry | Xiao F.,Key Laboratory of Applied Surface and Colloid Chemistry | Wang H.,Key Laboratory of Applied Surface and Colloid Chemistry | And 2 more authors.
Solar Energy Materials and Solar Cells | Year: 2016

Silver nanoparticle (Ag NP) enhanced back reflector (BR) has been used for effective light trapping in thin-film silicon solar cells. In this letter, we demonstrate experimentally that the photocurrent density of hydrogenated amorphous silicon-germanium alloy (a-SiGe:H) based solar cells are enhanced by as much as 3.0 mA/cm2 or 19.5% with medium sized (320 nm) Ag NPs as compared to the specular BR. In addition, it is demonstrated that the optimized Ag NP BR is also effective in multi-junction solar cells. It is believed that it is the appropriated surface morphology of the Ag NPs that leads to the improved light-trapping. It is found that the average haze of the Ag NP enhanced BR can be improved to as much as >70% throughout the wavelength range 600-900 nm. The atomic-force-microscopy measurement shows that the optimized root mean square roughness of Ag NP BR is about 35.2 nm. © 2015 Elsevier B.V. All rights reserved.


Yang L.-Q.,Key Laboratory of Applied Surface and Colloid Chemistry | Hao M.-M.,Key Laboratory of Applied Surface and Colloid Chemistry | Wang H.-Y.,Key Laboratory of Applied Surface and Colloid Chemistry | Zhang Y.,Key Laboratory of Applied Surface and Colloid Chemistry
Colloid and Polymer Science | Year: 2015

Environmentally sensitive polymer microgels are increasingly being used to enhance the catalytic activity of supported metal nanoparticles. Herein, we synthesized composite polymer microgels composed of the core–shell structure poly(styrene-N-isopropylacrylamide)/poly(N-isopropylacrylamide-co-methacrylic acid) (P(St-NIPAM)/P(NIPAM-co-MAA)). Ag nanoparticles (AgNPs) were loaded onto/into the network chains of the polymer microgels through a facile method. The prepared composite microgels were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, and ultraviolet-visible spectroscopy. The catalytic selectivity of P(St-NIPAM)/P(NIPAM-co-MAA)–Ag composite microgels for the reduction of hydrophilic 4-nitrophenol (4-NP) and hydrophobic nitrobenzene (NB) by NaBH4 was investigated. The results indicated that the introduction of PMAA segments into the microgel networks caused the poly(N-isopropylacrylamide) (PNIPAM) chains to separate into a shell layer and prevented the aggregation of AgNPs. The separated PNIPAM segments not only favor the mass transfer, but also possess thermosensitive function to modulate the catalytic activity of AgNPs. These structural features of the prepared composite microgels could enhance the selectivity and mass transfer of the reactants for catalytic reduction of 4-NP and NB through temperature modulation. © 2015, Springer-Verlag Berlin Heidelberg.


Wu Y.,Key Laboratory of Applied Surface and Colloid Chemistry | Liu K.,Key Laboratory of Applied Surface and Colloid Chemistry | Chen X.,Key Laboratory of Applied Surface and Colloid Chemistry | Chen Y.,Key Laboratory of Applied Surface and Colloid Chemistry | And 3 more authors.
New Journal of Chemistry | Year: 2015

A calix[4]arene-based dimeric-cholesteryl derivative with naphthalene in the linkers (C2N2C) was designed and synthesized. The gelation behaviors of the compound in 36 liquids were evaluated. It was demonstrated that C2N2C could gel 16 of the liquids tested, which include both polar and apolar liquids. SEM and AFM studies revealed that the morphologies of the gel networks are dependent on the concentrations of C2N2C and the nature of the liquids under study. Importantly, rheological studies revealed that the gel of the compound in benzene possesses sensitive, fast and fully reversible thixotropic property. More importantly, the Tgel of the C2N2C/benzene gel could be at least more than 60 degrees higher than the boiling point of benzene when the gelator concentration is greater than 6% (w/v), a result never reported before. CD measurements revealed the chiral nature of the assemblies of the gel networks. Further investigation by AFM measurements confirmed the right-hand helical structures of the gel networks of C2N2C/benzene gel. As anticipated, hydrogen bonding and π-π stacking are the two main driving forces for the formation of the gels. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2015.

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