Enhancement of hydrogen-storage properties of Mg by reactive mechanical grinding with oxide, metallic element(s), and hydride-forming element

Abstract

In order to improve the hydrogen-storage properties of magnesium, oxides, metallic element(s) and a hydride-forming element were added to Mg by grinding under a hydrogen atmosphere (reactive mechanical grinding). As the oxides, Fe2O3 purchased, Fe2O3 prepared by spray conversion, MnO purchased, SiO2 prepared by spray conversion, and Cr2O3 prepared by spray conversion were chosen. As the metallic elements, Ni, Fe, and Mo were selected. In addition, as the hydride-forming element, Ti was selected. Samples with the compositions of Mg–10wt%oxide, 76.5wt%Mg–23.5wt%Ni, 71.5wt%Mg–23.5wt%Ni–5wt% Fe2O3, 71.5wt%Mg–23.5wt%Ni–5wt%Fe, and Mg–14wt%Ni–2wt%Fe–2wt%Ti–2wt%Mo were prepared. The hydrogen-storage properties and changes in phase and microstructure after the hydriding–dehydriding cycling of the prepared samples were then investigated.