%0 Journal Article
%T Mechanism of the influence of the interaction between interstitial H atom and doped atom on the dehydrogenation performance of LiNH2<br>LiNH_2储氢材料中间隙H与掺杂原子交互作用对其释氢性能影响机理研究
%A Lu Guang-Xi
%A Zhang Hui
%A Zhang Guo-Ying
%A Liang Ting
%A Li Dan
%A Zhu Sheng-Long
%A <br>路广霞
%A 张辉
%A 张国英
%A 梁婷
%A 李丹
%A 朱圣龙
%J 物理学报
%D 2011
%I 
%X The first-principles plane-wave pseudopotential method based on the density functional theory is used to investigate the mechanism of the influence of interaction between interstitial H atom defect and doped atom on the dehydrogenation performance of LiNH2. We obtain the most stable structure of LiNH2 by geometrical optimization, and calculate the binding-energies, interstitial H atom defect formation energies, densities of states (DOSs), and electric charge populations for LiNH2 and doped LiNH2. Studies show that the results of binding-energy cannot reflect the dehydrogenating properties of LiNH2 and doped LiNH2. In equilibrium, there are a number of interstitial H atom defects; the formation energy of interstitial H atom defect is reduced by doping Mg and Ti, which increases the concentration of interstitial H atoms. Interstitial H atoms can induce the defect energy level in the gap, which reduces the width of the gap, and improves the dehydrogenation performance of LiNH2. The strength of N-H bond in NH2]- is weakened by interstitial H atom, so that hydrogen atoms in LiNH2 is relatively easy to release. The covalent bond between interstitial H atom and N atom of NH2]- explains the escape of NH3 from the dehydrogenation reaction of LiNH2 system. The strengths of N-H bonds are not equal in doped LiNH2, a part of N-H bonds are weaker, and other N-H bonds are strong, the hydrogen atoms are easy to release from weaker N-H bonds.
%K hydrogen storage materials
%K first-principles calculation
%K defect
%K dehydrogenation mechanics<br>储氢材料
%K 第一性原理
%K 缺陷
%K 释氢机理
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=29DF2CB55EF687E7EFA80DFD4B978260&aid=7FB288757ED284A0E5ADF6C38BB6ED70&yid=9377ED8094509821&vid=BFE7933E5EEA150D&iid=708DD6B15D2464E8&sid=3791BA7DCD009EE4&eid=3791BA7DCD009EE4&journal_id=1000-3290&journal_name=物理学报&referenced_num=0&reference_num=16