Advanced

Reactivity of LiBH4: In situ synchrotron radiation powder X-ray diffraction study

Mosegaard, Lene; Moller, Bitten; Jorgensen, Jens-Erik; Filinchuk, Yaroslav; Cerenius, Yngve LU ; Hanson, Jonathan C; Dimasi, Elaine; Besenbacher, Flemming and Jensen, Torben R (2008) In Journal of Physical Chemistry C 112(4). p.1299-1303
Abstract
Lithium tetrahydridoboranate (LiBH4) may be a potentially interesting material for hydrogen storage, but in order to absorb and desorb hydrogen routinely and reversibly, the kinetics and thermodynamics need to be improved significantly. A priori, this material has one of the highest theoretical gravimetric hydrogen contents, 18.5 wt%, but unfortunately for practical applications, hydrogen release occurs at too high temperature in a non-reversible way. By means of in situ synchrotron radiation powder X-ray diffraction (SR-PXD), the interaction between LiBH4 and different additives-SiO2, TiCl3, LiCl, and Au - is investigated. It is found that silicon dioxide reacts with molten LiBH4 and forms Li2SiO3 or Li4SiO4 at relatively low amounts of... (More)
Lithium tetrahydridoboranate (LiBH4) may be a potentially interesting material for hydrogen storage, but in order to absorb and desorb hydrogen routinely and reversibly, the kinetics and thermodynamics need to be improved significantly. A priori, this material has one of the highest theoretical gravimetric hydrogen contents, 18.5 wt%, but unfortunately for practical applications, hydrogen release occurs at too high temperature in a non-reversible way. By means of in situ synchrotron radiation powder X-ray diffraction (SR-PXD), the interaction between LiBH4 and different additives-SiO2, TiCl3, LiCl, and Au - is investigated. It is found that silicon dioxide reacts with molten LiBH4 and forms Li2SiO3 or Li4SiO4 at relatively low amounts of SiO2, e.g., with 5.0 and 9.9 mol % SiO2 in LiBH4, Whereas, for higher amounts of SiO2 (e.g., 25.5 mol %), only the Li2SiO3 phase is observed. Furthermore, we demonstrate that a solid-state reaction occurs between LiBH4 and TiCl3 to form LiCl at room temperature. At elevated temperatures, more LiCl is formed simultaneously with a decrease in the diffracted intensity from TiCl3. Lithium chloride shows some solubility in solid LiBH4 at T > 100 degrees C. This is the first report of substituents that accommodate the structure of LiBH4 by a solid/solid dissolution reaction. Gold is found to react with molten LiBH4 forming a Li-Au alloy with CuAu3-type structure. These studies demonstrate that molten LiBH4 has a high reactivity, and finding a catalyst for this H-rich system may be a challenge. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Physical Chemistry C
volume
112
issue
4
pages
1299 - 1303
publisher
The American Chemical Society
external identifiers
  • wos:000252619100056
  • scopus:39349099339
ISSN
1932-7447
DOI
10.1021/jp076999v
language
English
LU publication?
yes
id
59ab1a20-0010-470d-bf04-548e827cf3d7 (old id 1199058)
date added to LUP
2008-09-11 09:34:57
date last changed
2017-05-21 03:29:09
@article{59ab1a20-0010-470d-bf04-548e827cf3d7,
  abstract     = {Lithium tetrahydridoboranate (LiBH4) may be a potentially interesting material for hydrogen storage, but in order to absorb and desorb hydrogen routinely and reversibly, the kinetics and thermodynamics need to be improved significantly. A priori, this material has one of the highest theoretical gravimetric hydrogen contents, 18.5 wt%, but unfortunately for practical applications, hydrogen release occurs at too high temperature in a non-reversible way. By means of in situ synchrotron radiation powder X-ray diffraction (SR-PXD), the interaction between LiBH4 and different additives-SiO2, TiCl3, LiCl, and Au - is investigated. It is found that silicon dioxide reacts with molten LiBH4 and forms Li2SiO3 or Li4SiO4 at relatively low amounts of SiO2, e.g., with 5.0 and 9.9 mol % SiO2 in LiBH4, Whereas, for higher amounts of SiO2 (e.g., 25.5 mol %), only the Li2SiO3 phase is observed. Furthermore, we demonstrate that a solid-state reaction occurs between LiBH4 and TiCl3 to form LiCl at room temperature. At elevated temperatures, more LiCl is formed simultaneously with a decrease in the diffracted intensity from TiCl3. Lithium chloride shows some solubility in solid LiBH4 at T > 100 degrees C. This is the first report of substituents that accommodate the structure of LiBH4 by a solid/solid dissolution reaction. Gold is found to react with molten LiBH4 forming a Li-Au alloy with CuAu3-type structure. These studies demonstrate that molten LiBH4 has a high reactivity, and finding a catalyst for this H-rich system may be a challenge.},
  author       = {Mosegaard, Lene and Moller, Bitten and Jorgensen, Jens-Erik and Filinchuk, Yaroslav and Cerenius, Yngve and Hanson, Jonathan C and Dimasi, Elaine and Besenbacher, Flemming and Jensen, Torben R},
  issn         = {1932-7447},
  language     = {eng},
  number       = {4},
  pages        = {1299--1303},
  publisher    = {The American Chemical Society},
  series       = {Journal of Physical Chemistry C},
  title        = {Reactivity of LiBH4: In situ synchrotron radiation powder X-ray diffraction study},
  url          = {http://dx.doi.org/10.1021/jp076999v},
  volume       = {112},
  year         = {2008},
}