Study of the dehydrogenation behavior of magnesium hydride

The application of magnesium hydride as a hydrogen storage material has been limited by its high hydrogen release temperature. This study elucidates that the nucleation barrier for hexagonal close-packed (hcp)-Mg plays an important role in establishing the hydrogen release temperature. When the magnesium powders are hydrogenated such that the surface is completely covered by the hydride phase, the desorption temperature is found to be high, owing to the energy required for the nucleation of the hcp-Mg on the surface. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.