Efficient hydrogen generation from magnesium hydrolysis catalyzed by MoSi2/C

Magnesium holds significant promise as an on-site hydrogen generation material due to its high theoretical hydrogen yield, low cost, and environmental friendliness. However, its practical application is severely hindered by the magnesium hydroxide passivation layer formed during hydrolysis. In this study, a composite catalyst of molybdenum disilicide supported on coconut shell-derived activated carbon (MoSi 2 /C) was synthesized via a two-step calcination method and subsequently compounded with magnesium powder through ball milling. The as-prepared Mg-5wt% MoSi 2 /C composite exhibits remarkable hydrogen production performance via hydrolysis in a 3.5 wt% NaCl solution (simulating seawater). At 25 °C, it achieves a hydrogen yield of 916 mL/g within 90 s and a maximum hydrogen generation rate (mHGR) of 780 mL·g −1 ·min −1 , significantly outperforming pure Mg and a Mg-C composite. The apparent activation energy for the hydrolysis of this composite is notably reduced to 15.62 kJ mol −1 , indicating substantially enhanced reaction kinetics. The enhanced performance originates from the synergistic effect between the conductive carbon matrix and the highly dispersed MoSi 2 nanoparticles: the carbon matrix effectively prevents the agglomeration of Mg particles and facilitates electron transfer, while the MoSi 2 nanoparticles provide abundant active sites for the hydrolysis reaction. This work presents an efficient catalytic strategy for developing high-performance, low-cost magnesium-based materials for hydrogen production via hydrolysis.