Reversible hydrogen-storage functions for mixtures of Li3N and Mg3N2

The hydriding and dehydriding reactions occurring in mixtures of lithium and magnesium nitrides (Li3N and Mg3N2) were investigated for the first time in fixed composition ratios. A mixture of Li3N - 20 at.% Mg3N2 after heat treatment at 833 K was hydrogenated at 523 K in 35 MPa according to the following overall reaction: 4Li(3)N+ Mg3N2 + 12H(2) double left right arrow 12LiH + 3Mg( NH2)(2). This reaction is one of the candidates for reversible hydrogen-storage functions in which 9.1 mass% of hydrogen can be stored in the solid state.