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Solvent effects on structure and optical properties of a D-π-A azobenzene dye

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Chinese Physics B 2007年第11期16卷 3323-3327页

作者：王传奎邢晓娟黄晓明高云 College of Physics and Electronics Shandong Normal UniversityJinan250014China Department of Physics Heze CollegeHeze274015China

Time-dependent hybrid density functional theory in combination with Onsager reaction field model and super-molecular model has been applied to study Solvent effects on the geometrical and electronic structures, as well as one/two-photon absorption properties, of 4-（N-（2-hydroxyethyl）-N-methyl）-amino-4＇-nitroazobenzene. It is found that the short-range interaction has a large effect on the electronic structure of the solute molecule, namely, large red-shift of the maximum one-photon absorption is induced by hydrogen bonding. The solute molecule has a large two-photon absorption cross section, which is enhanced by the solvent effect. The computational results are in good agreement with measurements.

关键词： Solvent effects response theory hydrogen bonding two-photon absorption

Solvent effects on competitive intramolecular electron transfer and energy transfer in a covalently linked porphyrin-phthalocyanine heterodimer

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Chinese Journal of Chemistry 1996年第5期14卷 412-420页

作者： Tian, HJ Zhou, QF Shen, SY Xu, HJ ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Photophysical properties of a porphyrin-phthalocyanine heterodimer covalently linked with a dipentoxy chain have been studied. Absorption spectra show that there is weak exciton coupling between the two chromophores in the ground state. Fluorescence spectra show that intramolecular energy transfer from porphyrin to phthalocyanine moiety occurs in competition with electron transfer. The efficiency of these two processes depends upon the mutual orientation of the two chromophores. The effect of solvent, polarity on the intramolecular processes is also discussed.

关键词： Solvent effects electron transfer energy transfer porphyrin phthalocyanine

Effect of solvents on the morphology and structure of barium titanate synthesized by a one-step hydrothermal method

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1407-1416页

作者： Xiaoxiao Pang Tingting Wang Bin Liu Xiayue Fan Xiaorui Liu Jing Shen Cheng Zhong Wenbin Hu Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) and Tianjin Key Laboratory of Composite and Functional MaterialsSchool of Materials Science and EngineeringTianjin UniversityTianjin 300072China Chongqing Newcent New Materials Co. Ltd.Chongqing 401147China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

Tetragonal barium titanate was synthesized from barium hydroxide octahydrate and titanium tetrachloride through a simple one-step hydrothermal method.The effect of different solvents on the crystal structure and morphology of barium titanate nanoparticles during the hy-drothermal process was investigated.Except for ethylene glycol/water solvent,impurity-free barium titanate was synthesized in pure water,methanol/water,ethanol/water,and isopropyl alcohol/water mixed solvents.Compared with other alcohols,ethanol promotes the formation of a tetragonal structure.In addition,characterization studies confirm that particles synthesized in methanol/water,ethanol/water,and isopropyl al-cohol/water mixed solvents are smaller in size than those synthesized in pure water.In the case of alcohol-containing solvents,the particle size decreases in the order of isopropanol,ethanol,and methanol.Among all the media used in this study,ethanol/water is considered the optimum reaction media for barium titanate with high tetragonality(defined as the ratio of two lattice parameters c and a,c/a=1.0088)and small aver-age particle size(82 nm),which indicates its great application potential in multilayer ceramic capacitors.

关键词： barium titanate hydrothermal synthesis tetragonality Solvent effects

effects of Different solvent Baths on the Performance of Dye-Sensitized Solar Cells:Experimental and Theoretical Investigation

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Effects of Different Solvent Baths on the Performance of Dye...

Promoting Ethylene (co)Polymerization in Aliphatic Hydrocarbon solvents Using tert-Butyl Substituted Nickel Catalysts

第一届新型太阳能电池暨钙钛矿太阳能电池学术研讨会

作者： Ximing Chen Chunyang Jia Zhongquan Wan State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

Combining experimental analyses and computational modeling, we investigated CD-7-sensitized solar cells(DSSCs) by THF or DMF bath with aim to understand the effects of different solvent baths on the performance of the corresponding DSSCs. In experiment, the photophysical, photovoltaic and electrochemical impedance properties of CD-7-sensitized solar cells(DSSCs) by THF or DMF bath were investigated. The UV-vis spectra of CD-7 in THF solvent is red-shifted in comparison with it in DMF solvent, indicating that there is a different interaction between CD-7 and solvent molecules. The UV-vis spectra of CD-7 adsorbed on TiO film suggested that different solvent baths would lead to a different effect on the J-aggregation and adsorption strength. Monochromatic incident photon-to-electron conversion efficiency(IPCE) and electrochemical impedance analyses showed that different solvent baths have a significant influence on the IPCE value and the electron lifetime of the corresponding DSSCs. The analysis results of computational modeling showed that the solvent molecules would affect the adsorption structure of CD-7, energy level of TiO and the adsorbed amount of CD-7 on the TiO film. The above analysis results illuminate a big difference in the performance of CD-7-sensitized solar cells(DSSCs) by THF or DMF bath. CD-7-sensitized solar cells(DSSCs) by THF bath obtained the η value 1.53%, which is about twice as much as that of DMF bath.

关键词： Solvent effects TiO2 cluster Density functional theory（DFT） Photovoltaic performance Dye-sensitized solar cells（DSSCs）

来源： cnki会议评论

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Chinese Journal of Chemistry 2022年第2期40卷 215-222页

作者： Ao Chen Daohong Liao Changle Chen Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter ChemistryDepartment of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China

In the past few decades,the development of high-performance catalysts has been a key driving force and a center of research efforts in the field of olefin polymerization.However,a major discrepa ncy exists between in dustrial researches which utilize aliphatic hydrocarb on solventsz and academic researches which predominantly focus the catalytic properties in aromatic solvents.In this con-tribution,a novel diaryl-methyl aniline bearing eight tert-butyl groups was prepared and subsequently transformed to four different kinds of imine-type ligands.The corresponding nickel complexes as well as their counterparts derived from diphenyl-methyl aniline without the tert-butyl groups were prepared and investigated in ethylene polymerization.

关键词： Ethylene polymerization Polyethylene Nickel Solvent effects Steric hindranee

Force-Induced Enhancement of Hydrophilicity of Individual Polymethyl Methacrylate Chain

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Chinese Journal of Chemistry 2023年第18期41卷 2289-2295页

作者： Wenping Kang Yu Bao Hailong Wang Nanpu Cao Shuxun Cui School of Chemistry College of Life Science and EngineeringKey Lab of Advanced Technologies of Materials(Ministry of Education)Southwest Jiaotong UniversityChengduSichuan610031China

Comprehensive Summary,Polymethyl methacrylate(PMMA)has been widely applied in diverse fields such as medicine and engineering materials due to its good hydrophilicity and biocompatibility.However,another term for PMMA,Plexiglas,means that it is water insoluble.These features of PMMA are valuable but seem paradoxical.To explore the underlying mechanism of the paradoxical properties,the interactions between PMMA and water have been investigated by atomic force microscopy(AFM)-based single-molecule force spectroscopy(SMFS).The single-chain elasticity of PMMA obtained in aqueous solutions is significantly different from that obtained in non-aqueous environments,implying that PMMA can form hydrogen bonds with water molecules.

关键词： Polymethyl methacrylate Single-molecule studies Hydrogen bonding Hydrophilicity Solvent effects

Room-Temperature Reversibleσ-Dimerization of a Phenalenyl Radical

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Chinese Journal of Chemistry 2022年第14期40卷 1655-1661页

作者： Xue Dong Quanchun Sun Zhongtao Feng Huapeng Ruan Shuxuan Tang Min Liu Yue Zhao Yuanting Su Xinping Wang State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjingJiangsu 21023China Cllege of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhouiangsu 215123China

Phenalenyl derivatives have been of tremendous interest due to their reversible dimerization in response to the external stimuli such as temperature.However,most of PLY derivatives only show the reversibility dependent on temperature.Herein,we report a unique PLY-based radical anionic salt with reversibleσ-dimerization controlled by solvent rather than temperature.The structure and reversibility of this PLY anion system have been spectroscopically,crystallographically,and theoretically investigated.The molecule exists mainly as theσ-dimer form of K2[σ-12]in toluene,while it can be broken into the monomeric radical anion 1•–by re-dissolving in THF.Moreover,when THF is replaced with toluene,radical 1•–could beσ-dimerized back again.Theoretical calculations reveal that the potassium ions are necessary for the formation of theσ-dimer and the solvent polarity controls theσ-dimerization by regulating the presence of K+.

关键词： σ-Dimerization Solvent effects Reversible dimerization PLY Radicals

Small Molecule:Polymer Blends for N-type Organic Thin Film Transistors via Bar-coating in Air

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Chinese Journal of Chemistry 2022年第1期40卷 91-96页

作者： Xiaoyu Liu Yibo Shi Qian Zhou Jie Liu Lang Jiang Yang Han School of Materials Science and Engineering and Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin UniversityTianjin 300072China Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China

Fabricating n-type organic thin film transistors(OTFTs)based on small molecules via solution processing under atmospheric conditions remains challenging.Blending small molecules with polymer is an effective strategy to improve the solution processibility and air stability of the resulted devices.In this study,polystyrene was chosen to blend with n-type small molecule DPP1012-4F to enhance the continuity of the semiconductor layer and maintain a favorable edge-on stacking of semiconductors.The introduction of high-boiling point 1-chloronaphthalene as a solvent additive in the blending system can reduce the grain boundary defects in the microscopic morphology.These changes in aggregation behavior are confirmed by X-ray diffraction,atomic force microscopy and polarized optical microscopy analyses.Via bar-coating of the semiconductor layers in air,the electron mobility of the resulted OTFTs under the optimal condition is 0.73 cm2·V–1·s–1,which is amongst the highest n-type small molecule-based OTFTs with active layers prepared in air up to now.These results show a great potential of the blending strategy in industrial roll-to-roll manufacture of high-mobility n-type OTFTs.

关键词： Orga nicthin-film transistors Thin films Electron transport Blend materials Solvent effects

A Quantitative Study of Solvent effects on Keto-Enol Tautomeric Equilibria

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Chemical Research in Chinese Universities 1990年第1期6卷 76-79页

作者： Chen Zikang (Department of Chemistry, Beijing Normal University, Beijing)Zhang Yuejun (Elemento-Organic Chemistry Laboratory, Nankai University, Tianjin)

Introduction Organic compounds usually have labile bonds. It is well known that thousands of reactions are carried out in solutions, only a few in the gas-phase. Most chemists are now familiar with the fact that solvent may have a strong influence on reaction rate and equilibrium, so in the last decade, resarching the influence of Solvent effects on reaction rate and reaction equilibrium was a very important and

关键词： Solvent effects Keto-Enol tautomerism N-acetoacetylpyrrole