A first-principles study of the catalytic mechanism of the dehydriding reaction of LiNH2 through adding Ti catalysts

doi:10.1088/1674-1056/19/4/048601

IMR OpenIR

	A first-principles study of the catalytic mechanism of the dehydriding reaction of LiNH2 through adding Ti catalysts
	Zhang Hui 1; Liu Gui-Li 2; Qi Ke-Zhen 1; Zhang Guo-Ying 1; Xiao Ming-Zhu 1; Zhu Sheng-Long 3
通讯作者	Zhang Hui(huizhangking@sina.com)
	2010-04-01
发表期刊	CHINESE PHYSICS B
ISSN	1674-1056
卷号	19 期号:4 页码:6
摘要	Experiments on a ball milled mixture with a 1:1 molar ratio of LiNH2 and LiH with a small amount (1 mol %) of Ti-nano, TiCl3 and TiO2nano have revealed a superior catalytic effect on Li-N-H hydrogen storage materials. In the x-ray diffraction profiles, no trace of Ti-nano, TiCl3 and TiO2nano was found in these doped composites, by which we deduced that Ti atoms enter LiNH2 by partial element substitution. A first-principles plane-wave pseudopotential method based on density functional theory has been used to investigate the catalytic effects of Ti catalysts on the dehydrogenating properties of LiNH2 system. The results show that Ti substitution can reduce the dehydrogenation reaction activation energy of LiNH2 and improve the dehydrogenating properties of LiNH2. Based on the analysis of the density of states and overlap populations for LiNH2 before and after Ti substitution, it was found that the stability of the system of LiNH2 is reduced, which originates from the increase of the valence electrons at the Fermi level (E-F) and the decrease of the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap (Delta EH-L) near E-F. The catalytic effect of Ti on the dehydrogenating kinetics of LiNH2 may be attributed to the reduction of average populations between N-H per unit bond length (nm(-1)), which leads to the reduction of the chemical bond strength of N-H.
关键词	LiNH2 first-principles calculation dehydrogenating properties Ti catalytic mechanism
资助者	National High Technology Research & Development of China ; National Natural Science Foundation of China ; Education Bureau of Liaoning Province of China ; Shenyang Normal University
DOI	10.1088/1674-1056/19/4/048601
收录类别	SCI
语种	英语
资助项目	National High Technology Research & Development of China[2009AA05Z105] ; National Natural Science Foundation of China[50671069] ; Education Bureau of Liaoning Province of China[2008S345] ; Education Bureau of Liaoning Province of China[2008511] ; Education Bureau of Liaoning Province of China[2007T165] ; Shenyang Normal University
WOS研究方向	Physics
WOS类目	Physics, Multidisciplinary
WOS记录号	WOS:000276936200078
出版者	IOP PUBLISHING LTD
引用统计	被引频次：7[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/102860
专题	中国科学院金属研究所
通讯作者	Zhang Hui
作者单位	1.Shenyang Normal Univ, Coll Phys Sci & Technol, Shenyang 110034, Peoples R China 2.Shenyang Univ Technol, Coll Construct Engn, Shenyang 110023, Peoples R China 3.Chinese Acad Sci, Inst Met Res, State Key Lab Corros & Protect, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Zhang Hui,Liu Gui-Li,Qi Ke-Zhen,et al. A first-principles study of the catalytic mechanism of the dehydriding reaction of LiNH2 through adding Ti catalysts[J]. CHINESE PHYSICS B,2010,19(4):6.
APA	Zhang Hui,Liu Gui-Li,Qi Ke-Zhen,Zhang Guo-Ying,Xiao Ming-Zhu,&Zhu Sheng-Long.(2010).A first-principles study of the catalytic mechanism of the dehydriding reaction of LiNH2 through adding Ti catalysts.CHINESE PHYSICS B,19(4),6.
MLA	Zhang Hui,et al."A first-principles study of the catalytic mechanism of the dehydriding reaction of LiNH2 through adding Ti catalysts".CHINESE PHYSICS B 19.4(2010):6.