Hydrogen storage characteristics of nanocrystalline and amorphous Mg2Ni-type alloys prepared by melt spinning

▶ The investigation on the structures of the as-cast and spun Mg2Ni1−xMnx (x = 0, 0.1, 0.2, 0.3, 0.4) alloys shows that there is no amorphous phase in the as-spun Mn-free alloy, but the as-spun alloys containing Mn present an evident feature of the nanocrystalline embedded in the amorphous matrix. The amorphization degree of the alloys visibly increases with rising spinning rate. ▶ Melt spinning considerably enhances not only the electrochemical discharge capacity of the alloys but also the electrochemical cycle stability of the alloys containing Mn. But it slightly impairs cycle stability of the Mn-free alloy, for which the different structure formed by the melt spinning is basically responsible. ▶ Melt spinning significantly improves the hydriding and dehydriding properties of the alloys. Hydriding and dehydriding capacities and rates of the alloy markedly increase with rising spinning rate.