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The reaction between magnesium amide and hydride at a molar ratio of 1:2 by means of mechanical ball mining has resulted in the release of a stoichiometric amount of [H.sub.2] and the formation of magnesium nitride. Thermodynamic calculations have shown that the hydrogen release reaction of [1Mg[(N[H.sub.2]).sub.2] + 2Mg[H.sub.2] is mildly endothermic, but the low reaction enthalpy has predicted impractical operation conditions of the hydrogen uptake reaction.

A total of 7.4 wt % of hydrogen was released from the mixture of magnesium amide and magnesium hydride at a molar ratio of 1:2 by mechanical ball milling. Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) characterizations along with the amount of hydrogen released at different stages of ball milling reveal that magnesium imide was first formed in the reaction. The imide then reacted continuously with magnesium hydride and was converted to magnesium nitride and hydrogen. Thermodynamic calculation shows that the hydrogen desorption is a mild endothermic reaction with the standard enthalpy change of about 3.5 kJ/mol of H2.