Synergistic catalytic effects of Ni MOF catalyst and RE alloying on the hydrogen absorption/desorption kinetics of MgH2

The Mg90Ce5Y5 + x wt. % Ni MOF (x = 0, 3) composites were prepared successfully and we investigated the synergistic catalytic effects of Ni MOF catalyst doping and RE alloying for the hydrogen storage properties of pure Mg. The N3 sample absorbs about 3.05 wt. % H2 at 473 K within 2 min, while the pure Mg almost does not initiates reaction at the same condition. The Edes of N3 only is calculated as 69.0 & PLUSMN; 3.9 kJ/mol and much lower than pure MgH2 (160 kJ/mol). The improved hydrogen storage kinetics is considered that the CeH2.73 and YH2 phases provide nucleation sites and channels of diffusion inside the particle and the extra Ni active positions, defects and cracks facilitate H2 dissociation/recombination, generated by Ni MOF on the particle surface.