Abstract
The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride(MgH2)in sustainable energy devices.Herein,FeCoNiCrTi high-entropy alloy(HEA)nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH2 to boost the hydrogen storage per-formance.The refined HEA exhibited superior catalytic activity on MgH2.In contrast to additive-free MgH2,the initial desorption temperature of the constructed MgH2-HEA composite was reduced from 330.0 to 198.5 ℃ and a remarkable 51％reduction in the dehydrogenation activa-tion energy was achieved.Besides,the MgH2-HEA com-posite only required one-twentieth time of that consumed by pure MgH2 to absorb 5.0 wt％of H2 at 225 ℃.The synergy between the"hydrogen pumping"effect of Mg2Ni/Mg2NiH4 and Mg2Co/Mg2CoH5 couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH2 contributed to the enhanced de/hydrogenation per-formance of the MgH2-HEA composites.This study fur-nishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.
基金项目
National Natural Science Foundation of China(51801078)
NETL
NSTL
万方数据