Hydrogen-storage properties of Mg-oxide alloys prepared by reactive mechanical grinding

The samples Mg-10 wt.% M (M=Fe2O3 purchased, Fe2O3 by spray conversion, MnO purchased, and SiO2 by spray conversion) were prepared by mechanical grinding under H-2 (reactive mechanical grinding) under the optimum conditions for the preparation of the sample Mg-10 wt.% Fe2O3 using purchased Fe2O3. The activated Mg-10 wt.% Fe,03 by spray conversion has the highest hydriding rate (H-a = 5.55 wt.% at 593 K, 12 bar H-2 for 60 min) of all the samples. The activated Mg-10 wt.% MnO has the highest dehydriding rate (H-d = 1.94 wt.% at 593 K, 1.0 bar H-2 for 60 min). The equilibrium plateau pressure is about 1.5 bar H-2. The effects of reactive mechanical grinding and hydriding-dehydriding cycling on the hydrogen properties of Mg were discussed. (c) 2005 Elsevier B.V. All rights reserved.