Lithium hexahydridoaluminate Li3AlH6 and lithium-amide LiNH2 with 1:2 molar ratio were mechanically milled, yielding a Li-AI-N-H system. LiNH2 destabilized Li 3AlH6 during the dehydrogenation process of Li 3AlH6, because the dehydrogenation starting temperature of the Li-AI-N-H system was lower than that of Li3AlH6. Temperature-programmed desorption scans of the Li-AI-N-H system indicated that a large amount of hydrogen (6.9 wt %) can be released between 370 and 773 K. After initial H2 desorption, the H2 absorption and the desorption capacities of the Li-AI-N-H system with a nano-Ni catalyst exhibited 3-4 wt % at 10-0.004 MPa and 473-573 K, while the capacities of the system without the catalyst were 1-2 wt %. The remarkably increased capacity was due to the fact that the kinetics was improved by addition of the nano-Ni catalyst.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry