Abstract

Hydrogen desorption and absorption properties of two destabilized systems, 6LiBH4 + CeH2 + 0.2TiCl3 (Ce system) and 6LiBH4 + CaH2 + 0.2TiCl3 (Ca system), have been characterized. The theoretical hydrogen capacity is 7.39 and 11.67 wt % for the Ce and Ca systems, respectively. Both systems follow the thermodynamically predicted dehydrogenation reaction path, forming LiH and metal hexaborides (MB6) as the dehydrogenated products, which is confirmed by X-ray diffraction data. After hydrogenation at 623 K (Ce system) or 673 K (Ca system) under 100 bar H2 pressure for 20 h, LiH + MB6 was converted back to the initial reactants, LiBH4 + MH2. The amount of H2 released during the first and the second dehydrogenation proves that the first dehydrogenation−hydrogenation cycle is fully reversible. The temperature required to achieve the reversibility is lower in the case of the Ce system, in agreement with our thermodynamic calculation. Our study is the first report of reversible hydrogen storage in 6LiBH4 + CeH2; this composite is one of the few destabilized systems shown to be fully reversible at this relatively low temperature range with a reasonably high hydrogen capacity.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.