First-principles Calculation of Electronic Structure and Dehydrogenating Properties of MgH2-Nb Systems

被引：0

作者：

Zhou Dianwu ^{[1
]}

Zhang Jian ^{[2
]}

Xu Shaohua ^{[3
]}

Peng Ping ^{[3
]}

Liu Jinshui ^{[3
]}

机构：

[1] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China

[2] Changsha Univ Sci & Technol, Sch Vehicle & Mech Engn, Changsha 410114, Peoples R China

[3] Hunan Univ, Sch Mat Sci & Engn, Changsha 410082, Peoples R China

来源：

ACTA CHIMICA SINICA | 2010年 / 68卷 / 10期

关键词：

MgH2; first-principles calculation; dehydrogenating properties; electronic structure; HYDROGEN; DESORPTION; ENERGETICS;

D O I：

暂无

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A NbH0 6/MgH2 interface is designed and constituted in this work. A first-principles plane-wave pseudopotentials method based on Density Functional Theory (DFT) has been used to investigate the Niobium alloying effects on the dehydrogenating properties and electronic structure of magnesium hydride, i e., MgH2 A low absolute value of the negative heat of formation of NbH0 6/MgH2 interface compared with that of MgH2 indicates Niobium hydrides befit to improve the dehydrogenating properties of MgH2. Based on the analysis of the density of states (DOS) and the total electron density distribution of MgH2 before and after Nb alloying, it was found that the catalysis effect of Nb on dehydrogenating kinetics of MgH2 may attribute to a stronger bonding between Nb and H atoms than that between Mg and H atoms, which leads to nucleation of NbH0 6 phase and the alpha-Mg at the NbH0 6/MgH2 interface in the MgH2-Nb systems is easier than in pure MgH2 phase

引用

页码：955 / 960

页数：6

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