Effect of Nd content on electrochemical performances of nanocrystalline and amorphous (Mg24Ni10Cu2)100−xNdx (x=0−20) alloys prepared by melt spinning

Abstract

The nanocrystalline and amorphous Mg2Ni-type alloys with a chemical composition of (Mg24Ni10Cu2)100−xNdx (x=0, 5, 10, 15, 20) were fabricated by melt spinning technology. The effects of spinning rate on the structure and electrochemical hydrogen storage performance of the alloys were investigated. The as-spun Nd-free alloy displays an entire nanocrystalline structure, whereas the as-spun Nd-added alloys hold a nanocrystalline and amorphous structure, suggesting that the addition of Nd facilitates the glass forming of the Mg2Ni-type alloys. Increasing the spinning rate from 0 to 40 m/s gives rise to the discharge capacity growing from 42.5 to 100.6 mA·h/g for the x=0 alloy and from 86.4 to 452.8 mA·h/g for the x=10 alloy. And the cycle stability (S20) rises from 40.2% to 41.1% for the x=0 alloy and from 53.2% to 89.7% for the x=10 alloy, respectively.