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Chinese Chemical Letters 2023年第2期34卷 550-556页

作者： Jinrong Huo Haocong Wei Ling Fu Chenxu Zhao Chaozheng He School of Sciences Xi'an Technological UniversityXi'an 710021China Shaanxi Key Laboratory of Optoelectronic Functional Materials and Devices School of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China Institute of Environmental and Energy Catalysis School of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China College of Resources and Environmental Engineering Tianshui Normal UniversityTianshui 741001China

In this paper,Fe_(36)Co_(44)nanocluster structure is used to catalyze the hydrolysis reaction of ammonia borane to produce H_(2).firstly,we complete the construction of Fe_(36)Co_(44)cluster structure and calculate the electronic properties of the cluster.By comparing the adsorption process of Ammonia Borane (AB) in active sites of the cluster,which have different Effective Coordination Number (ECN),the qualitative relationship between ECN and the catalytic activation of AB is clarified,and the optimal catalytic active site is obtained.Then,from the perspective of different reaction paths,we study the hydrolysis reaction of AB in multiple paths,and obtain 5 different reaction paths and energy profiles.The calculation results show that in the case of N–H bond priority break (path 5),the reaction has the minimum rate-determining step (RDS) barrier (about 1.02 e V) and the entire reaction is exothermic (about 0.40 e V).So,path 5 is an optimal catalytic reaction path.This study will have an important guiding significance for the study of the AB hydrolysis reaction mechanism.

关键词： the first-principles NH_(3)BH_(3) Hydrolysis reaction FeCo cluster Catalyst

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the first-principles Study on the Rectification of Molecular Junctions Based on the Alkyl-chain-modified[2,5?]Bipyrimidinyl(biphenyl isocyanide)gold(Ⅰ)

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Chinese Journal of Structural Chemistry 2020年第10期39卷 1763-1769,1741页

作者：高泉党杨娥 College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Using density functional theory(DFT)combined with nonequilibrium Green?s function investigates the electron-transport properties of several molecular junctions based on the[2,5?]bipyrimidinyl(biphenyl isocyanide)gold(Ⅰ)molecule(BPM-Au(Ⅰ)CN-BP),which is modified by one to three alkyl groups forming BPM-Au(Ⅰ)CN-BP(CH2)n.The asymmetric current-voltage characteristics have been obtained for the molecular junctions.Rectifying performance of Au/S-BPM-Au(I)CN-BP-S/Au molecular junction can be regulated by introducing alkyl chain.The M1 molecular junction exhibits the best rectifying effect.Its maximum rectifying ratio is 2109,which is about 150 times more than that of the molecular junction based on the original M.Moreover,all the systems modified by alkyl group have obvious negative differential resistance behavior(NDR).The current-voltage(Ⅰ-Ⅴ)curves of all the systems in this work are illustrated by transmission spectra.

关键词： the first-principles isocyanide gold(Ⅰ)compound alkyl chain rectifying ratio

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the first-principles study on the doping effect of Re in Ni3Al

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Progress in Natural Science:Materials International 2008年第7期18卷 861-866页

作者： Song Yu a,*, Chongyu Wanga,b, Tao Yua aCentral Iron and Steel Research Institute, Beijing 100081, China bDepartment of Physics, Tsinghua University, Beijing 100084, China Central Iron and Steel Research Institute Beijing 100081 China Department of Physics Tsinghua University Beijing 100084 China

Using first-principles density function for molecules method (DMol) and discrete variational method (DVM) based on the density functional theory, we studied the doping effect of Re in Ni3Al. The structure relaxation and the alloying energy show that Re has a strong Al site preference and leads to the local deformation, which is in agreement with the experimental results and other theoretical results. In addition, the charge density diffierence and the bond order show that Re can strongly enhance the interatomic interaction between the nearest neighbor atoms. From the density of states and the Pauli spectrum, we find that resonance states and localized states are induced by doping Re, and the doped Re atom forms the hybridized bond with the nearest neighbor atoms.

关键词： the first-principles Re Ni3Al

Theoretical Predition of Two-dimensional SiGeP_(2)by the Global Optimization Method

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1010-1016页

作者： XUE Xiao YU Jiahui ZHOU Dawei PU Chunying School of Information Engineering Nanyang Institute of TechnologyNanyang 473004China School of Mathematics and Physics Nanyang Institute of TechnologyNanyang 473004China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang473061China

The well-developed particle-swarm optimization method together with density functional theory calculations were employed to search lowest-energy geometric structures of two-dimensional(2D)SiGeP_(2).Two newly found structures(P3m1 and Pmm2)are predicted.The unbiased global search reveals that the two lowest-energy structures are honeycomb lattices with robust dynamical stabilities.A more accurate Heyd-Scuseria-Ernzerhof(HSE06)hybrid functional is used to estimate the band structures of SiGeP_(2),which indicates that both the structures are semiconductors with indirect band-gap energies 1.80 e V for P3m1 and1.93 e V for Pmm^(2),respectively.Using the deformation potential theory,the P3m1-SiGeP_(2)is predicted to have high electron mobilities(6.4×10^(4)along zigzag direction and 2.9×10^(3)cm^(2)·V^(-1)·s^(-1)along armchair direction,respectively)and hole electron mobilities(1.0×10^(3)along zigzag direction and 2.5×10^(3)cm^(2)·V^(-1)·s^(-1)along armchair direction,respectively),which can be comparable with that of phosphorene and show anisotropic character in-plane.In addition,to estimate the elastic limit of SiGeP_(2),we also calculated the surface tension of SiGeP_(2)as a function of tensile strain.Our results show that the 2D SiGeP_(2)may be good candidaticates for applications in nanoelectronic devices.

关键词： two dimensional SiGeP_(2) the first-principles carrier mobility

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Structural and electronic properties of Fe-doped BaTiO3 and SrTiO3

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Chinese Physics B 2007年第5期16卷 1422-1428页

作者：张超王春雷李吉超杨鲲 School of Physics and Microelectronics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

We have performed first principles calculations of Fe-doped BaTiO3 and SrTiO3. Dopant formation energy, structure distortion, band structure and density of states have been computed. The dopant formation energy is found to be 6.8eV and 6.5eV for Fe-doped BaTiO3 and SrTiO3 respectively. The distances between Fe impurity and its nearest O atoms and between Fe atom and Ba or Sr atoms are smaller than those of the corresponding undoped bulk systems. The Fe defect energy band is obtained, which mainly originates from Fe 3d electrons. The band gap is still an indirect one after Fe doping for both BaTiO3 and SrWiO3, but the gap changes from Γ-R point to Γ-X point.

关键词： the first-principles impurity BaTiO3 SrTiO3