Developing a suitable on□ board hydrogen storage material is a key technical barrier to safeand efficient hydrogen storage technology.1. - Among all the complex metal hydrides, lithium alanate (L1AlH_4) is of particularinterest. However, the practical application of LiAlH_4 is limited by its relatively slow dehydrogenation rate and poorreversibility.~(3-6)To overcome these drawbacks, different kinds of nitrides, including NbN, TiN and BN, are synthesized innanosize and added to L1AlH_4. The catalytic effects of these nitrides on the kinetics and thermodynamics of LiAlH_4are discussed in detail. All these nanostructured nitrides can effectively improve the dehydrogenation performances ofLiAlH_4. For example, 2%NbNnanoplate—LiAlH_4 sample starts to decompose at about 95 °C and releases 7.10 wt. %hydrogen, which is 55 °C lower than that of as—milled LiAlH_4. The activation energy (E_a) is calculated to be 71.91 and90.87 kJ mol~(-1) for the first and second hydrogen desorption of 2%NbN—LiAlH_4sample, a 38% and 32% reductionrelative to as-received LiAlH_4, respectively. Other nitrides, BN and TiN, can also enhance the dehydrogenationperformances of L1AlH_4 in different degrees.
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