High dehydrogenation temperature and slow dehydrogenation kinetics impede the practical application of magnesium hydride (MgH₂) serving as a potential hydrogen storage medium. In this paper, Fe–Ni catalyst modified three-dimensional graphene was added to MgH₂ by ball milling to optimize the hydrogen storage performance, the impacts and mechanisms of which are systematically investigated based on the thermodynamic and kinetic analysis. The MgH₂+10 wt%Fe–Ni@3DG composite system can absorb 6.35 wt% within 100 s (300 °C, 50 atm H₂ pressure) and release 5.13 wt% within 500 s (300 °C, 0.5 atm H₂ pressure). In addition, it can absorb 6.5 wt% and release 5.7 wt% within 10 min during 7 cycles, exhibiting excellent cycle stability without degradation. The absorption-desorption mechanism of MgH₂ can be changed by the synergistic effects of the two catalyst materials, which significantly promotes the improvement of kinetic performance of dehydrogenation process and reduces the hydrogen desorption temperature.

高脱氢温度和缓慢的脱氢动力学阻碍了氢化镁 (MgH ₂ ) 作为潜在储氢介质的实际应用。在本文中，通过球磨将Fe-Ni 催化剂改性的三维石墨烯加入MgH ₂以优化储氢性能，并基于热力学和动力学分析系统地研究其影响和机理。MgH ₂ +10 wt% Fe-Ni@3DG 复合体系可以在 100 s（300 °C，50 atm H ₂压力）内吸收 6.35 wt%，并在 500 s（300 °C，0.5 atm H ₂压力）内释放 5.13 wt%压力）。此外，它可以在 7 个循环中在 10 分钟内吸收 6.5 wt% 并释放 5.7 wt%，表现出优异的循环稳定性而不会降解。两种催化剂材料的协同作用可以改变MgH ₂的吸附-解吸机理，显着促进了脱氢过程动力学性能的提高，降低了氢的解吸温度。