Excellent catalysis of MoO3 on the hydrogen sorption of MgH2

To improve the hydrogen sorption kinetics of MgH 2 , the MoO 3 nanobelts were added into MgH 2 by mechanical milling, leading to fine distribution of MoO 3 in the MgH 2 matrix. Compared to uncatalyzed MgH 2 , the hydriding and dehydriding rates of MoO 3 -catalyzed MgH 2 were significantly improved. The MgH 2 doped with 2 mol% MoO 3 exhibited fast dehydrogenation without activation, and the initial dehydrogenation amount of 5 wt% could be reached within 900 s at 300 °C. The dehydrogenation apparent activation energy is decreased down to 114.7 kJ/mol. The excellent catalytic effect of MoO 3 originates from its specific role as fast hydrogen diffusion pathways. In the hydrogenation process , the MoO 3 transformed to MoO 2 , resulting in the fading of catalytic activity .