Hydrogen-storage properties of a Mg-based mixture prepared by reactive mechanical grinding with ultrafine Fe2O3 particles and Ni

The sample Mg-10 wt.% (Fe2O3, Ni) was prepared by grinding Mg mechanically under H2 (reactive mechanical grinding) with ultrafine Fe2O3 particles and Ni particles. The sample Mg-10 wt.% (Fe2O3, Ni) as milled absorbed 4.24 wt.% hydrogen at 593 K under 12 bar H2 for 60 min. Its activation was accomplished only by one hydriding–dehydriding cycle. The activated sample absorbed 4.05 wt.% hydrogen at 593K, 12 bar H2 for 60 min and desorbed 3.05 wt.% hydrogen at 593 K, 1.0 bar H2 for 60 min. After hydriding–dehydriding cycling, Fe2O3 was reduced, Mg2Ni was formed by the reaction of Mg with Ni, and a small fraction of Mg was oxidized.