关键词：贮氢合金;激活;金属玻璃氢原子;纳米晶微结构
摘 要：An amorphous Mg85Ni15 melt-spun hydrogen storage alloy, processed by submersion in an aqueous solution of NH4 +, is able to absorb >5 wt.hydrogen at 473 K during the first hydrogenation cycle. The nanocrystalline microstructure formed during devitrification of the metallic glass is preserved by the lower required activation temperature of the NH4 +- treated material; and the kinetics of subsequent absorption/desorption cycles at 573 K are dramatically improved, compared to the as-spun material. DSC experiments and thermodynamic calculations demonstrate that the decreased crystallite size of the 473 K activated material lowers the hydride decomposition temperature by 20 K to 50 K, in contrast to a sample activated at 573 K. The NH4 +- treatment of a glassy alloy presented here provides a more practical approach to both forming a nanocrystalline material, and facilitating activation, compared to ball milling; requiring much less time and a more commercially scalable option.