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Chinese Journal of Structural chemistry 2011年第5期30卷 622-629页

作者：林霏吴克琛和建刚洒荣建李巧红韦永勤 State Key Laboratory of Structural chemistry Laboratory of Theoretical and Computational ChemistryFujian Institute of Research on the Structure of MatterChinese Academy of Sciences

In this paper, density functional computations have been applied to the structural, elastic and electronic properties of ternary transition metal diborides Re0.5Ir0.5B2, Re0.5Tc0.5B2, Os0.5W0.5B2 and Os0.5Ru0.5B2 in hexagonal （P63/mmc） and orthorhombic （Pmmn） structures with both local density approximation and generalized gradient approximation. LDA gives smaller lattice parameters and larger elastic moduli than GGA. Both results show that the hexagonal ones are more stable than orthorhombic ones except Os0.5Ru0.5B2. Moreover, the hexagonal structure has superior elastic property than orthorhombic one. Generally speaking, the calculated elastic moduli of Re0.5Ir0.5B2 and Os0.5Ru0.5B2 are smaller than those values of Re0.5Tc0.5B2 and Os0.5W0.5B2 within the same structure because of the filling of antibonding states. The relativistic effects result in weaker bonds of Tc-B （Ru-B） than those of Re-B （Os-B）. All the diborides are ultra-incompressible. Re0.5Tc0.5B2 has the largest shear modulus and it is a promising superhard diboride like Os0.5W0.5B2. The elastic properties are in high correlation with the bond strength. The shear moduli are more sensitive than the bulk moduli to the bond strength.

关键词： transition metal borides elastic moduli density functional study,ultra-incompressible

DFT study on adduct reaction paths of GaN MOCVD growth

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Science China(Technological Sciences) 2013年第7期56卷 1644-1650页

作者： SHI JunCao ZUO Ran MENG SuCi School of Energy and Power Engineering Jiangsu University chool of chemistry and Chemical Engineering Jiangsu University institute of Theoretical Computational chemistry Key Laboratory of Mesoscopic Chemistry of Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University

The adduct reaction paths for GaN growth by metal organic chemical vapor deposition (MOCVD) were studied by quantum chemical calculations employing density functional theory (DFT). Five possible adduct reaction paths with or without the ex-cess NH3were proposed and the corresponding potential energy surfaces were calculated. From the calculation results, it is concluded that after the formation of DMGNH2from TMG:NH3, the further decomposition paths have very slim probability because of the high energy barriers; whereas the oligomerization pathway to form oligomers [DMGNH2]x(x=2, 3) is probable,because of zero energy barrier. Since the oligomers tend to further polymerize, the nanoparticles are easily formed through this path. When NH3is in excess, TMG:NH3 tends to combine with the second NH3to form two new complexes: the coordination-bonded compound H3N:TMG:NH3and the hydrogen-bonded compound TMG:NH3 NH3. The formation of hydrogen-bonded compound TMG:NH3 NH3 will be more probable because of the lower energy than H3N:TMG:NH3. By comparing the potential energy surfaces in five adduct reaction paths, we postulate that, under the growth conditions of GaN MOCVD, the formation of hydrogen-bonded compound TMG:NH3 NH3 followed by the reversible decomposition may be the main reaction path for GaN thin film growth; while the adduct oligomerization path to generate oligomers [DMGNH2]2 and [DMGNH2]3might be the main reaction path for nanoparticles formation.

关键词： metal organic chemical vapor deposition (MOCVD) GaN adduct reaction quantum chemical calculation densityfunctional theory (DFT)

Rational confinement engineering of MOF-derived carbonbased electrocatalysts toward CO_(2)reduction and O_(2)reduction reactions

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InfoMat 2022年第3期4卷 34-63页

作者： Xiaoyu Zhang Dongping Xue Su Jiang Huicong Xia Yanlin Yang Wenfu Yan Jinsong Hu Jianan Zhang College of Materials Science and Engineering Zhengzhou UniversityZhengzhouP.R.China Academic Publishing Center Henan Polytechnic UniversityJiaozuoP.R.China State Key Laboratory of inorganic Synthesis and Preparative chemistry and College of ChemistryJilin UniversityChangchunP.R.China Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of ChemistryChinese Academy of SciencesBeijingP.R.China

The goal of global carbon peak and neutrality gives an impetus to the utilization of clean energy(e.g.,fuel cell)and carbon dioxide(CO_(2))at a large scale,where the oxygen reduction reaction(ORR)and CO_(2)reduction reaction(CO_(2)RR)are the key reactions via the sustainable system,*** a main precursor for fabricating affordable carbon-based electrocatalysts with uniformly dispersed active centers and tailorable performances for ORR and CO_(2)RR,metal organic frameworks(MOFs)have captured a surge of interest in recent *** the facilitated development of MOF-derived carbon-based electrocatalysts by many investigations,it is still plagued by high overpotential and unsatisfied life span,which are greatly determined by the efficient and alterable confinement effect on synthesis and *** this review,firstly,the confined synthetic strategies(doping engineering,defect engineering,geometric engineering,etc.)of MOF-derived carbon-based electrocatalysts with multi-sized active centers(atom,atomic clusters and nanoparticles(NPs))are systematically summarized;secondly,the confinement effect on the interaction of ORR and CO_(2)RR intermediates,as well as the catalytic durability and activity,was discussed from chemical and physical *** the end,the review discusses the remaining challenges and emerging research topics in the future,including support upgradation and catalyst innovation,high selectivity and effective confinement synthesis,in situ and operando characterization techniques,theoretical investigation,and artificial intelligence(AI)*** new understanding and insights into these aspects will guide the rational confinement concept of MOF-derived carbon-based electrocatalysts for ORR and CO_(2)RR with optimized performances in terms of confinement engineering and are believed to be helpful for filling the existing gaps between scientific communities and practical use.

关键词： carbon-based materials CO_(2)reduction reaction confinement effect electrocatalyst metal organic framework oxygen reduction reaction

Physicochemical Properties of Thin Rhenium Chalcogenides Coatings

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Journal of Materials Science and Chemical Engineering 2015年第11期3卷 82-87页

作者： E. A. Salakhova D. B. Tagiyev P. E. Kalantarova K. F. Ibrahimova Lab. of Electrodeposition of Rhenium Alloys and Electrocatalysis Institute of Catalysis and Inorganic Chemistry NAS of Azerbaijan Baku Azerbaijan

Some physicochemical properties of thin layers of rhenium chalcogenides alloys such as micro-hardness and inner tension have been investigated. An influence of electrolyte composition and content of rhenium in the alloy on inner tension and microhardness of rhenium chalcogenides alloy was studied. It is established that the electrolytic alloys of rhenium chalcogenides obtained from different electrolytes possess inner tension of stretching. The most favourable condition for reaching the uniform coating of rhenium chalcogenides from sulphate and chloride-sulphate electrolyte using dispersive capacity (DC) of electrolyte has been found out. The best DC in chloride-sulphate and sulphate electrolyte takes place at current density of 0.8 A/dm2 at 75℃.

关键词： Electrochemistry Thin Films Rhenium Chalcogenides Rhenium Alloys

High Speed Boundary Layer Stability and Control

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High Speed Boundary Layer Stability and Control

Extraction-Atomic-Absorption Determination of Gallium (III) with 2-hydroxy-5-T-butylphenol-4’-methoxy-azobenzene

第六届国际流体力学会议

作者： A. A. Maslov Khristianovich institute of Theoretical and Applied Mechanics sb ras Novosibirsk 630090RussiaNovosibirsk State UniversityNovosibirsk 630090Russia

In the present paper an overview of the recent studies of a hypersonic laminar boundary layer and shock layer receptivity and stability are *** attention is paid to investigations of nonlinear wave *** is shown that nonlinear interactions of the second mode play significant role in laminar-turbulent transition and intermode interaction is different for solid and porous *** paper deals with two different techniques of transition *** first one,namely,ultrasonically absorptive coating（UAC） is a passive technique which uses porous materials on the wall to suppress growing acoustic disturbances in the boundary *** second one is based on wave interference and intermode interaction and uses blowing-suction method to suppress acoustic in the boundary layer.

关键词： boundary layer shock layer disturbance development nonlinear interaction passive and active distur-bances control

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Journal of Materials Science and Chemical Engineering 2020年第9期8卷 24-30页

作者： Aydin M. Pashajanov Shahin M. Bayramov Gulu G. Abbasova Melek M. Agamaliyeva Zumrud A. Mamedova ANAS institute of Catalysis and inorganic chemistry Named after Acad. M. Naghiyev Baku Azerbaijan

The complexation of gallium with 2-hydroxy-5-T-butylphenol-4’-methoxy-azobenzene (HR) has been studied by atomic absorption and spectrophotometric methods. The optimal conditions for the formation and extraction of the complex were found. The maximum light absorption of the complex in n-butanol is in the range of 450 - 470 nm. The molar absorption coefficient is (3.3 - 4.2)⋅104. The stability constant of the gallium coordination compound in n-butanol is βl = 4.2⋅1010. The developed technique allows to determine the gallium content within n × 10−1 - n × 10−4%. The selective and sensitive technique for the extraction-atomic absorption determination of gallium in soils has been developed.

关键词： Gallium Complexing Atomic Absorption Method Extraction Gallium in Soil

Progress in molecular materials and devices

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Chinese Science Bulletin 2013年第22期58卷 2667-2668页

作者： ZHU DaoBen ZHANG DeQing Academician of Chinese Academy of Sciences institute of chemistry Chinese Academy of Sciences institute of chemistry Chinese Academy of Sciences

Initial studies on organic semiconductors began in the early 1960s in *** the 1970s,a specialized laboratory(***.6)was established at the institute of chemistry,Chinese Academy of Sciences(ICCAS),which housed the firs... 详细信息

关键词：单分子器件高分子材料中国科学院化学研究所有机半导体材料国家自然科学基金会有机场效应晶体管有机发光二极管有机太阳能电池

Addition Reactivity of C_(36) Cage Controlled by the Curvature and the Electronic Factors:A DFT Study

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Chinese Journal of Structural chemistry 2012年第1期31卷 131-138页

作者：陈林刚陈勇肖河阳李浩宏李俊篯 Department of chemistry Fuzhou University State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences

The molecular geometries and electronic structures of the fullerene derivatives C36（OH）n（n = 1～2） have been investigated on the basis of density functional theory calculation at the B3LYP/6-31＋＋G＊ *** geometry optimization results indicate that the location of C2 atom is the most active site in the three potential adding patterns,and the C1 or C2 site has a larger binding energy than C3 for the addition reactions of C36（D6h） cage and OH radicals resulting from the larger *** electronic structure calculation results disclose that the C2 site has larger electronic population in HOMO and larger spin density,and the addition reaction on the C2 site need overcome a lesser energy gap than that on the C1 or C3 ***,the addition is controlled jointly by the curvature and the electronic ***,when two hydroxyls are added to the C36 surface,the C2 sites are also the most active *** most stable addition adduct of C36（OH）2 is the isomer which holds Ci symmetry,and the spin multiplicity seriously affects the stabilities of the adducts.

关键词： C36 C36(OH)2 curvature first-principle addition reaction

Structural Tuning of Low Band Gap Intermolecular Push/Pull Side-chain Polymers for Organic Photovoltaic Applications

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Chinese Journal of Polymer Science 2017年第9期35卷 1073-1085页

作者： Ansuman Nayak P.S. Rama Sreekanth Santosh Kumar Sahu Duryodhan Sahu Department of chemistry National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008 Department of chemistry Gandhi Institute of Engineering and Technology Gunpur Odisha India Department of Mechanical Engineering National Institute of Science and Technology Palur Hills Berhampur Odisha India 761008

A series of novel low band gap donor-acceptor （D-A） type organic co-polymers （BT-F-TPA, BT-CZ-TPA and BT-SI-TPA） consisting of electron-deficient acceptor blocks both in main chains （M1） and at the pendant （M2） were polymerized with different electron rich donor （M3-M5） blocks, i.e., 9,9-dihexyl-9H-fluorene, N-alkyl-2,7-carbazole, and 2,6-dithinosilole, respectively, via Suzuki method. These polymers exhibited relatively low band gaps （1.65-1.88 eV） and broad absorption ranges （680-740 nm）. Bulk heterojunction （BHJ） solar cells incorporating these polymers as electron donors, blended with [6,6]-phenyl-C61-butyric acid methyl ester （PC61BM） or [6,6]-phenyl-Cvl-butyric acid methyl ester （PC71BM） as electron-acceptors in different weight ratios were fabricated and tested under 100 mW/cm2 of AM 1.5 with white-light illumination. The photovoltaic device containing donor BT-SI-TPA and acceptor PC71BM in 1：2 weight ratio showed the best power conversion efficiency （PCE） value of 1.88%, with open circuit voltage （Voc） = 0.75 V, short circuit current density （Jsc） = 7.60 mA/cm2, and fill factor （FF） = 33.0%.

关键词： Polymer solar cells Low band gap Conducting polymers Charge transfer Donor-acceptor Bulk heterojunctionsolar cell

Thickness Uniformity Adjustment of Inkjet Printed Light-emitting Polymer Films by Solvent Mixture

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Chinese Journal of chemistry 2013年第11期31卷 1449-1454页

作者： Rubo Xing Tengling Ye Yan Ding Zicheng Ding Dongge Ma Yanchun Han State Key Laboratory of Polymer Physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

In this paper, thickness uniformity of poly（9,9-di-n-octylfluorene） films patterned by inkjet printing was im- proved by the use of solvent mixtures （a solvent with higher volatility, higher surface energy and lower viscosity, with another solvent with lower volatility, lower surface energy and higher viscosity）. The average thickness of inkjet printed poly（9,9-di-n-octylfluorene） films was increased from ca. 30 nm to ca. 100 nm when solvent mixtures were used instead of pure chlorobenzene. More flat PFO films were formed instead of the original films with con- cave-lens like cross-section formed by coffee ring effect. This improvement was explained by combination of in- tense Marangoni flow at early drying process and weak complementary flow at the later drying process formed in the solvent mixture. Patterned poly（9,9-di-n-octylfluorene） films were used for fabrication of electroluminescence devices with improved electronic property. Array of pixels with about 80% effective light-emitting area was ob- tained.

关键词： inkjet printing solvent mixtures thickness uniformity organic light-emitting diodes marangoni flow,coffee ring effect