jp411551v_si_001.pdf (391.01 kB)
NH3 Mediated or Ion Migration Reaction: The Case Study on Halide–Amide System
journal contribution
posted on 2014-02-06, 00:00 authored by Hujun Cao, Jianhui Wang, Yongshen Chua, Han Wang, Guotao Wu, Zhitao Xiong, Jieshan Qiu, Ping ChenLively
debates on hydrogen desorption from the amide–hydride system
via either ion migration or NH3 mediated mechanisms have
been ongoing since the discovery of the amide–hydride system
for hydrogen storage. In this work, we employed kinetic analyses to
demonstrate that the mechanism of hydrogen desorption depends on the
sample morphology and desorption conditions. Upon the formation of
Li amide bromide (Li2NH2Br), the LiNH2 unit is confined in the cage of Br, resulting in less mobility of
ion. Hydrogen desorption from the Li2NH2Br–2LiH
system appears to follow the NH3 mediated mechanism even
if the two starting chemicals have been intensively ball milled. On
the other hand, the migrations of Li+ and H+ play important roles leading to H2 formation from the
direct combination of H+ (from −NH2)
and H– (from LiH) when LiNH2 and LiH
are intimately in contact.