Improved hydrogen storage kinetics of nanocrystalline and amorphous Ce-Mg-Ni-based CeMg12-type alloys synthesized by mechanical milling

Yanghuan Zhang; Pengpeng Wang; Wengang Bu; Zeming Yuan; Yan Qi; Shihai Guo

doi:10.1039/c8ra03393e

Improved hydrogen storage kinetics of nanocrystalline and amorphous Ce-Mg-Ni-based CeMg₁₂-type alloys synthesized by mechanical milling

RSC Adv. 2018 Jun 27;8(41):23353-23363. doi: 10.1039/c8ra03393e. eCollection 2018 Jun 21.

Authors

Yanghuan Zhang^{1

2}, Pengpeng Wang^{1

2}, Wengang Bu², Zeming Yuan^{1

2}, Yan Qi², Shihai Guo²

Affiliations

¹ Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology Baotou 014010 China.
² Department of Functional Material Research, Central Iron and Steel Research Institute Beijing 100081 China zhangyh59@sina.com.

Abstract

In this paper, ball milling was used to prepare CeMg₁₁Ni + x wt% Ni (x = 100, 200) alloys having nanocrystalline and amorphous structures. The structures of the alloys and their electrochemical and gaseous kinetic performances were systematically investigated. It was shown that the increase in Ni content was beneficial to the formation of nanocrystalline and amorphous structures, and it significantly enhanced the electrochemical and gaseous hydrogen storage performances of as-milled alloys. In addition, the hydrogen storage capacities of the alloys fluctuated greatly with variation in milling duration. The maximum values of hydrogen capacity detected by varying the milling durations were 5.949 wt% and 6.157 wt% for x = 100 and 200 alloys, respectively. Similar results were observed for the hydriding rates and high-rate discharge abilities (HRD) of the as-milled alloys. The dehydriding rate increased with the increase in milling duration. The reduction in hydrogen desorption activation was the reason for enhanced gaseous hydrogen storage kinetics.