RE-oxide doped alkaline hydrogen storage materials prepared by mechanical activation

In the hydrogen energy system, hydrogen storage materials are considered to play an important role, such as H-2 storage and transportation media. In case of fuel-cell powered vehicles, storage material with large capacity and light weight are required. Alanates e.g., NaAlH4, Na3AlH6 or Na2LiAlH6 have many advantages as hydrogen storage materials, because of their large hydrogen capacity, abundant in the earth crust and lower costs, etc. Alanates are, therefore, promising candidates for practical hydrogen transportation media, while investigations on their reaction kinetics with hydrogen are still insufficient. In this study, we prepared Na2LiAlH6 samples with different kinds of RE-oxides doped in the course of ball-milling. RE-oxides were used for improving hydrogen reactivity. Drastically improved hydrogen absorption kinetics obtained were discussed using thermodynamic consideration. (C) 2004 Kluwer Academic Publishers.