First-principles study of decomposition mechanisms of Mg(BH 4 ) 2 ·2NH 3 and LiMg(BH 4 ) 3 ·2NH 3

Citation data:

RSC Advances, ISSN: 2046-2069, Vol: 7, Issue: 49, Page: 31027-31032

Publication Year:
2017
Usage 18
Downloads 18
Captures 2
Readers 2
Citations 2
Citation Indexes 2
Repository URL:
http://ro.uow.edu.au/aiimpapers/2633
DOI:
10.1039/c7ra05322c
Author(s):
Chen, Xiaowei; Li, Renquan; Xia, Guanglin; He, Hongsheng; Zhang, Xiuqing; Zou, Weidong; Yu, Xubin
Publisher(s):
Royal Society of Chemistry (RSC); The Royal Society of Chemistry
Tags:
Chemistry; Chemical Engineering; mg(bh4)2$2nh3; limg(bh4)3$2nh3; first-principles; study; decomposition; mechanisms; Engineering; Physical Sciences and Mathematics
article description
The decomposition mechanisms of Mg(BH)·2NHand LiMg(BH)·2NHwere studied by using density functional theory calculations. Compared to that of Mg(BH)·2NH, the incorporation of LiBHwith the formation of LiMg(BH)·2NHslightly increased Bader charges of B atoms, meanwhile it decreased Bader charges of N atoms. Mg(BH)·2NHshows a low ammonia vacancy diffusion barrier, but relatively high ammonia vacancy formation energy, which lead to a low concentration of NHvacancies and limit NHtransportation. In contrast to that of Mg(BH)·2NH, LiMg(BH)·2NHhas a relatively high ammonia vacancy formation energy and diffusion barrier, which suppresses ammonia release. The incorporation of LiBHand Mg(BH)·2NHdoes not decrease but increases the hydrogen formation barrier of LiMg(BH)·2NH, resulting in a slight increase in the dehydrogenation peak temperature, consistent with experimental results.