Modification of MgH(2) hydrogen storage performance by nickel-based composite catalyst Ni/NiO

In this study, the Ni/NiO catalyst was demonstrated to enhance the hydrogen storage performance of MgH(2). The dehydrogenation of MgH(2)+10 wt% Ni/NiO started at approximately 180 °C, achieving 5.83 wt% of dehydrogenation within 10 min at 300 °C. Completely dehydrogenated, MgH(2) began to rehydrogenate at about 50 °C, absorbing about 4.56 wt% of hydrogen in 10 min at 150 °C. In addition, the activation energies of dehydrogenation and rehydrogenation of MgH(2)+10 wt% Ni/NiO were 87.21 and 34.84 kJ/mol. During the dehydrogenation/rehydrogenation cycle, Mg(2)Ni/Mg(2)NiH(4) could promote hydrogen diffusion, thus enhancing the hydrogen storage performance of Mg/MgH(2).