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Revealing interfacial charge redistribution of homologous Ru-RuS_(2) heterostructure toward robust hydrogen oxidation reaction

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Journal of Energy Chemistry 2024年第7期94卷 332-339页

作者： Yi Liu Lianrui Cheng Shuqing Zhou Yuting Yang Chenggong Niu Tayirjan Taylor Isimjan Bao Wang Xiulin Yang Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004GuangxiChina State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Saudi Arabia Basic Industries Corporation(SABIC)at King Abdullah University of Science and Technology(KAUST) Thuwal 23955-6900Saudi Arabia

Precisely tailoring the surface electronic structures of electrocatalysts for optimal hydrogen binding energy and hydroxide binding energy is vital to improve the sluggish kinetics of hydrogen oxidation reac-tion(HOR).Herein,we employ a partial desulfurization strategy to construct a homologous Ru-RuS_(2) heterostructure anchored on hollow mesoporous carbon nanospheres(Ru-RuS_(2)@C).The disparate work functions of the heterostructure contribute to the spontaneous formation of a unique built-in electric field,accelerating charge transfer and boosting conductivity of ***,Ru-RuS_(2)@C exhibits robust HOR electrocatalytic activity,achieving an exchange current density and mass activity as high as 3.56 mA cm^(-2) and 2.13 mAμg_(Ru)^(-1),*** those of state-of-the-art Pt/C and most contemporary Ru-based HOR ***,Ru-RuS_(2)@C can tolerate 1000 ppm of cO that lacks in Pt/*** analysis reveals that the directional electron transfer across Ru-RuS_(2) heterointerface induces local charge redistribution in interfacial region,which optimizes and balances the adsorption energies of H and OH species,as well as lowers the energy barrier for water formation,thereby promoting theHoR performance.

关键词： Heterostructure Hollow spherical structure Hydrogen oxidation reaction Charge redistribution density functional calculation

Revealing the Solution Structure of Pd(OAc)_(2) with Halide Additives

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Chinese Journal of Chemistry 2022年第8期40卷 895-901页

作者： Liwei Wang Dali Yang Hesham Alhumade Hong Yi Xiaotian Qi Aiwen Lei Institute for Advanced Studies(IAS) College of Chemistry and Molecular SciencesEngineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)Wuhan UniversityWuhanHubei 430072China King Abdulaziz University JeddahSaudi Arabia Department of Chemical andMaterials Engineering Facultyof EngineeringCenter of Research Excellence in Renewable Energy andPowerSystemsKingAbdulaziz UniversityJeddah21589Saudi Arabia

Mechanistic studies of the palladium catalyst activation with halide additives are of great importance to palladium *** this work,XAFS spectroscopy and cyclic voltammetry were utilized to study real structures of Pd(OAc)2 in solution with different inorgan-ic halogen *** results demonstrate that Pd maintained+2 in the presence of excessive LiCl,LiBr,ZnCl_(2),ZnBr_(2),and *** results of EXAFS spectra revealed that the Pd's first shell is replaced by halogen partially or completely depending on the hal-ogen *** calculations were conducted to identify the most reliable solvated *** combined experimental and computational studies elucidate the critical role of inorganic halide additives in Pd chemistry.

关键词： Palladium Structure Halides X-ray absorption spectroscopy(XAS) density functional calculation

Decomposition of Al_(13) promoted by salicylic acid under acidic condition: Mechanism study by differential mass spectrometry method and DFT calculation

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Journal of Environmental Sciences 2023年第4期126卷 423-433页

作者： Guangyu An Ye Yue Lian Yang Hailu Demissie Ruyuan Jiao Jinyang Xi Dongsheng Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Faculty Water Conservancy and Hydropower Engineering North China Electric Power UniversityBeijing 10220China Department of Chemistry Arba Minch UniversityArba Minch 021Ethiopia Yangtze River Delta Branch Research Center for Eco-Environmental SciencesChinese Academy of SciencesZhejiang 322000China Materials Genome Institute Shanghai UniversityShanghai 200444China College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China

Decomposition of the polycation Al_(13)O_(4)(OH)_(2)4(H_(2)O)_(12)^(7+)(Al_(13)) promoted by ligand is a vital subject to advance our understanding of natural and artificial occurrence and evolution of aluminum ions,especially in the case of acidic condition that dissolved Al^(3+)species can be released from the Al-bearing ***,the microscopic pathway of synchronous proton-promoted and ligand-promoted decomposition process for Al_(13)is still in the status of ***,we applied differential mass spectrometry method and DFT calculation to study the initial detailed process of Al_(13)decomposition under the presence of proton and salicylic acid (H_(2)Sal).Mass results showed that the mononuclear Al^(3+)-H_(2)Sal complexes dominated the resulting Al species,whereas the monodentate complex Al_(13)HSal6+was not observed in the *** difference of decomposition levels between the ligand/Al ratio 0.2 and 0.5 cases revealed that proton and ligand performed synergistic effect in initial Al_(13)decomposition process,and the proton transfer determined the ring closure *** ring closure reaction is the prerequisite for the collapse of Al_(13)structure and detachment of the mononuclear *** calculations reveal that hydrogen bond plays an important role in inducing the formation of chelated complex accompanying proton *** of protons at the bridging OH^(-)can elongate and weaken the critical bond between targeted Al^(3+)and μ4-O_(2)-resulting from delocalization of electron pairs in the oxygen *** results demonstrate the detailed mechanism of Al_(13)composition promoted by ligand and proton,and provide significant understanding for further application and control of Al_(13).

关键词： Al_(13) Differential mass spectrometry density functional calculation Complex Ring closure Decomposition

Ab initio study of oxygen-vacancy LaAlO_3(001) surface

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Chinese Physics B 2008年第2期17卷 655-661页

作者：唐金龙朱俊秦文峰熊杰李言荣 State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

density functional theory is used to investigate the surface structures and the energies of two possible terminated LaAlO3 （001） surfaces with oxygen vacancies, i.e. LaO- and AlO2-terminated surfaces. The large displacements of ions, deviated from their crystalline sites, can lead to the formation of the surface rumpling. From thermodynamics analysis, the AlO2-terminated surface with oxygen-vacancies is less stable than the LaO-terminated one. Some states in the gap lie under the Fermi level by about -1eV in the LaO-terminated surface with oxygen vacancies. For the AlO2- terminated oxygen-vacancy surface, some O 2p states move into the mid-gap region and become partially unoccupied. The two types of termination surfaces exhibit conduction related to oxygen vacancies. Our results can contribute to the application of LAO films to high dielectric constant materials.

关键词： oxygen vacancy surface conduction density functional calculation

Mechanism of Gold（I）-Catalyzed Conia-ene Reaction of β-Ketoesters with Alkynes： A DFT Study

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Chinese Journal of Chemistry 2011年第11期29卷 2320-2326页

作者：尹艳春王勉王坚毅周龙昌段文贵 School of Chemistry and Chemical Engineering Guangxi University Nanning Guangxi 530004 China Department of Pharmacy Guangxi Health College of Technology Nanning Guangxi 530023 China

density functional calculations have been performed to comparatively investigate two possible pathways of Au（I）-catalyzed Conia-ene reaction of β-ketoesters with alkynes. Our studies find that, under the assistance of trifluoromethanesulfonate （TfO）, the β-ketoester is the most likely to undergo Model II to isomerize into its enol form, in which TfO plays a proton transfer role through a 6-membered ring transition state. The coordination of the Au（I） catalyst to the alkynes triple bond can enhance the eletrophilic capability and reaction activity of the alkynes moiety, which triggers the nucleophilic addition of the enol moiety on the alkynes moiety to give a vinyl-Au intermediate. This cycloisomerizaion step is exothermal by 21.3 kJ/mol with an energy barrier of 56.0 kJ/mol. In the whole catalytic process, the protonation of vinyl-Au is almost spontaneous, and the formation of enol is a rate-limiting step. The generation of enol and the activation of Au（I） catalyst on the alkynes are the key reasons why the Conia-ene reaction can occur in mild condition. These calculations support that Au（I）-catalyzed Conia-ene reactions of β-ketoesters with alkynes go through the pathway 2 proposed by Toste.

关键词： Au(I) catalyst isomerization alkyne Conia-ene reaction density functional calculation

Infrared Photodissociation Spectra of Mass-Selected Homoleptic Dinuclear Palladium Carbonyl Cluster Cations in the Gas Phase

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Chinese Journal of Chemistry 2012年第9期30卷 2131-2137页

作者：崔洁铭邢小鹏池超贤王冠军刘智攀周鸣飞 Department of Chemistry Shanghai Key Laboratory of Molecular Catalysts and Innovative MaterialsFudan UniversityShanghai 200433China Graduate University of Chinese Academy of Sciences College of Materials Sciences and Opto-Electronic Tech-nologyBeijing 100049China

Infrared spectra of mass-selected homoleptic dinuclear palladium carbonyl cluster cations Pd2（CO）n （n=5 8） are measured via infrared photodissociation spectroscopy in the carbonyl stretching frequency region. The structures are established by comparison of the experimental spectra with simulated spectra derived from density functional calculations. The Pd2（CO）＋ cation is characterized to have two weakly semibridging CO groups with C2 symmetry. The Pd2（CO）6＋ and Pd2（CO）7＋ cations are determined to involve one weakly semibridging CO group. The Pd2（CO）8＋ cation is a CO coordination saturated cluster, which is determined to have a D2d structure with all of the carbonyl groups terminally bonded. Bonding analysis indicates that these cluster cations each has a Pd--Pd half bond. The Pd--Pd distance increases with the number of CO ligands.

关键词： metal carbonyl cluster palladium-palladium bonding density functional calculation infrared spectrum

First-Principle Studies on Adsorption of Cu^+ and Hydrated Cu^+ Cations on Clean Si(111) Surface

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Chemical Research in Chinese Universities 2010年第3期26卷 472-478页

作者： CHENG Feng-ming SHENG Yong-li LI Meng-hua LIU Yong-jun YU Zhang-yu LIU Cheng-bu School of Chemistry and Chemical Engineering School of Environmental Science and Engineering Shandong University Jinan 250100 P. R. China School of Chemistry and Chemical Engineering University of Jinan Jinan 250022 P. R. China

To study the adsorption behavior of Cu^＋ in aqueous solution on semiconductor surface, the interactions of Cu^＋ and hydrated Cu^＋ cations with the clean Si（111） surface were investigated via hybrid density functional theory（B3LYP） and Moller-Plesset second-order perturbation（MP2） method. The clean Si（111） surface was described with cluster models（Si14H17, Si16H20 and Si22H21） and a four-silicon layer slab under periodic boundary conditions. calculation results indicate that the bonding nature of adsorption of Cu^＋ on Si surface can be viewed as partial covalent as well as ionic bonding. The binding energies between hydrated Cu^＋ cations and Si（111） surface are large, suggesting a strong interaction between them. The coordination number of Cu^＋（H2O）n on Si（111） surface was found to be 4. As the number of water molecules is larger than 5, water molecules form a hydrogen bond network. In aqueous solution, Cu^＋ cations will safely attach to the clean Si（111） surface.

关键词： Silicon surface Copper Ion-solid interaction Adsorption density functional calculation

Insertion of O—H Bond of Rh(Ⅱ)-methylene Carbene into Alcohols: A Stepwise Mechanism More Plausible than a Concerted Mechanism

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Chemical Research in Chinese Universities 2007年第2期23卷 221-225页

作者： LIU Zhen-feng WANG Yong YUE Xian-fang HAN Ke-li State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dcdian 116023 P. R. China

The mechanisms of insertion of O-H bond of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol were studied by using B3LYP functional both in gas phase and in CH2 C12. The formation of free alcoholic oxonium ylides is found to be impossible. Alcoholic oxonium ylide are formed as the intermediates before beth the stepwise and the concerted transition states of insertion of O-H bend of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol. With re- gard to the mechanisms of insertion of O-H of Rh（ Ⅱ ） -methylene carbene into alcohols, analysis of the energy bartiers of the two mechanisms indicate that the stepwise mechanism is more plausible than the concerted mechanism.

关键词： Oxonium ylide 1,2-Hydrogen shift density functional calculation Dirhodium( Ⅱ ) methylene carbene

First principles calculations of electronic and optical properties of GaN_(1-x)Bi_x alloys

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Journal of Semiconductors 2014年第12期35卷 5-7页

作者：闫映策王琦马会芳 Department of Physics Taiyuan Normal University StateKey Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

The electronic and optical properties of the ternary GaN1-xBix alloys in the zinc-blende structure are theoretically investigated by first principles calculations. Geometric optimization is performed before all the simulations to get accurate results. The band gaps of the alloys are found to be direct even with xD6.25%, and would become smaller when increasing the Bi compositions. The decrease ratio of band gaps is approximately 227 me V when 1% of N is replaced by Bi in the range of xD0–6.25%. Meanwhile, the absorption coefficient is shown to be significantly changed induced by the incorporation of Bi. These interesting properties indicate that GaN1-xBix alloys could be a promising candidate in future optoelectronic applications.

关键词： Ga NBi density functional calculation electronic structures optical properties