Hydriding and dehydriding rates and hydrogen-storage capacity of Mg–14Ni–3Fe2O3–3Ti prepared by reactive mechanical grinding

Abstract

The magnesium prepared by mechanical grinding under H2 (reactive mechanical grinding) with transition elements or oxides showed relatively high hydriding and dehydriding rates when the content of additives was about 20 wt%. Ni (expected to increase hydriding and dehydriding rates) was chosen as transition element to be added. Fe2O3 (expected to increase hydriding rate) was selected as an oxide to be added. Ti was also selected since, it was considered to increase the hydriding and dehydriding rates by forming Ti hydride. A sample, Mg–14Ni–3Fe2O3–3Ti, was prepared by reactive mechanical grinding and its hydrogen storage properties were investigated. This sample absorbed 4·02 wt% H for 5 min, 4·15 wt% H for 10 min and 4·42 wt% H for 60 min at n = 2. It desorbed 2·46 wt% H for 10 min, 3·98 wt% H for 30 min and 4·20 wt% H for 60 min at n = 2.