Advancements in Solid Hydrogen Storage: Enhancing The Performance of MgH2-Based Materials

Magnesium hydride (MgH2) has attracted significant attention as a promising material for solid-state hydrogen storage due to its high gravimetric hydrogen capacity (7.6 wt%), low cost, natural abundance, and relative safety. These advantages make MgH2 a viable candidate for sustainable hydrogen energy systems. However, its practical application remains hindered by inherent limitations, including sluggish hydrogen sorption kinetics, high decomposition temperatures (typically above 300 °C), and unfavorable thermodynamic properties. To address these challenges, various enhancement strategies have been explored. Nanostructuring and particle size reduction techniques have been employed to shorten diffusion paths and increase surface reactivity. Alloying MgH2 with transition metals and rare-earth elements has improved hydrogen uptake through the formation of catalytic interfaces. In addition, doping with catalysts such as metal oxides, carbon-based materials, and intermetallic compounds has effectively reduced activation energy and accelerated reaction rates. Notably, alloying and the formation of composite materials have enabled the development of heterogeneous structures with enhanced reactivity and improved thermodynamic behavior. Beyond material-level improvements, heat management strategies and reactor design innovations have been investigated to ensure efficient heat transfer and system-level integration. This review summarizes recent advances in improving MgH2 for hydrogen storage, highlighting approaches from material modification to system design. The insights presented contribute to the advancement of efficient, reusable, and scalable hydrogen storage technologies for clean energy applications.