Hydrogen storage properties of amorphous and nanocrystalline (Mg24Ni10Cu2)100-xNdx (x=0-20) alloys

The as-cast and spun (Mg24Ni10Cu2)(100-x)Nd-x (x = 0-20) alloys were prepared in this experiment to study their hydrogen storage performances. The alloys were tested on composition, structure, de-/hydriding kinetics and electrochemical property in many ways including XRD, SEM, TEM, Sieverts apparatus and automatic galvanostatic system. It was found that each as-cast alloy is multi-phased, including Mg2Ni-type major phase and some second phases of Mg6Ni, Nd6Mg41 and NdNi, the proportion of which obviously increases with Nd content rising. After being melt spinning, the structure of no-Nd-added alloy is nanocrystalline, while the Nd-added alloy holds an amorphous and nanocrystalline structure, whose amorphization degree rises significantly with Nd content increasing. The hydrogen storage kinetics of alloys can be improved by the addition of Nd significantly. Besides, adding Nd results in the electrochemical discharge capacity of the as-spun alloy augments at first and declines later as well as cycle stability. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.