Jump to main content
Jump to site search

Issue 39, 2013
Previous Article Next Article

Ca(BH4)2–LiBH4–MgH2: a novel ternary hydrogen storage system with superior long-term cycling performance

Author affiliations

Abstract

A ternary hydrogen storage system, of superior cyclic stability and high capacity, was developed from a mixture of Ca(BH4)2, LiBH4 and MgH2 in molar ratios of 1 : 2 : 2. Investigation on both non-isothermal and isothermal hydrogen desorption/absorption properties shows that the hydrogen desorption starts from 320 °C and completes at 370 °C under a heating rate of 2 °C min−1, releasing ca. 8.1 wt% H2. The finishing temperature of desorption is much lower and the capacity much higher than any of the two-hydride mixtures in the ternary system. In particular, hydrogenation of the ternary system initiates at an extremely low temperature of ca. 75 °C and the onset dehydrogenation temperature is significantly reduced by 90 °C after the initial dehydrogenation/hydrogenation cycle, which is ascribed to the formation of an active dual-cation hydride of CaMgH3.72 for dehydrogenation in the hydrogenation process. There is ca. 7.6 wt% H2 absorbed at 350 °C and 90 bar H2 for 18 h for the system post-dehydrogenated at 370 °C for 30 min, demonstrating a reversibility of over 94%. The capacity seems to fade mainly in the initial few cycles and stabilizes after further cycling. The reversibility is as high as 97% and a dehydrogenation capacity of ca. 6.2 wt% H2 at the 10th cycle. Favourable kinetics and thermodynamics of hydrogen desorption/absorption are achieved, which are responsible for the low completion temperature and the superior cycling performance. Mechanisms of the improved dehydrogenation/hydrogenation properties including the cyclic behaviour of the system are also proposed in relation to microstructural analyses.

Graphical abstract: Ca(BH4)2–LiBH4–MgH2: a novel ternary hydrogen storage system with superior long-term cycling performance

Back to tab navigation

Supplementary files

Article information


Submitted
25 Jun 2013
Accepted
07 Aug 2013
First published
08 Aug 2013

J. Mater. Chem. A, 2013,1, 12285-12292
Article type
Paper

Ca(BH4)2–LiBH4–MgH2: a novel ternary hydrogen storage system with superior long-term cycling performance

M. Gao, J. Gu, H. Pan, Y. Wang, Y. Liu, C. Liang and Z. Guo, J. Mater. Chem. A, 2013, 1, 12285 DOI: 10.1039/C3TA12472J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.


Social activity

Search articles by author

Spotlight

Advertisements