Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5146126 | International Journal of Hydrogen Energy | 2017 | 11 Pages |
Abstract
Mg-Ni alloys are among the most promising candidates for solid-state hydrogen storage systems. This paper reveals the effect of Na doping in accelerating initial hydrogen uptake in Mg-Ni alloys using in-situ Synchrotron X-ray powder diffraction. A minimum concentration of approximately 0.2Â wt.% Na must be achieved for the alloys to show reasonably fast hydriding kinetics. Surface analysis shows that a Na-modified Mg-Ni surface facilitates the chemisorption and dissociation of hydrogen molecules in the early stage of hydriding as evidenced by a rapid formation of the saturated hydrogen solid solution Mg2NiH0.3 from the original Mg2Ni. The subsequent hydrogen absorption is based on a mechanism of nucleation and growth of MgH2 where a high density of dislocations develops ahead of the growing hydride-metal interface.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Xuan Quy Tran, Stuart D. McDonald, Qinfen Gu, Xin Fu Tan, Kazuhiro Nogita,