Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5147617 | International Journal of Hydrogen Energy | 2017 | 10 Pages |
Abstract
Target improving the hydrogen sorption properties of Mg, core-shell structured Mg@TM (TM = Co, V) composites were synthesized via an approach combining arc plasma method and electroless plating. The core-shell structures with the MgH2 core and V or Co containing hydride shells for hydrogenated Mg@TM particles were observed through HAADF-STEM and HRTEM techniques. The measured hydrogenation enthalpy (ÎHabs = â70.02 kJ/mol H2) and activation energy (Ea = 67.66 kJ/mol H2) of the ternary Mg@Co@V composite were lower than those of binary composites and the pure Mg powder. In addition, the onset dehydrogenation temperature for the hydrogenated ternary composite measured from DSC was 323 °C, about 60 °C lower than that of pure MgH2. On one hand, these improved properties can be attributed to the core-shell structure which may introduce more contacts between catalysts and Mg, thus providing more nucleation sites for hydrogen sorption. On the other hand, the co-effect of MgCo hydrides (Mg2CoH5&Mg3CoH5) acting as “hydrogen pump” and V2H accelerating the dissociation of H2 might also contribute to the improved hydrogen sorption properties of Mg.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Chong Lu, Jianxin Zou, Xiaoqin Zeng, Wenjiang Ding,