Advances in modification approaches for Mg-based hydrogen storage materials

As one of the most promising new energy sources, hydrogen energy is expected to usher in a full-fledged “hydrogen economy” in the 21st century. Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods, solid-state chemical hydrogen storage shows significant advantages in safety, high efficiency, and cost-effectiveness. Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density (7.6%) and favorable reversibility. However, their sluggish reaction kinetics and stringent operating conditions (with H2 release temperatures exceeding 350 °C and H2 absorption pressures above 4 MPa) pose major challenges for practical applications. Domestic and international researchers have conducted in-depth studies to address these issues, achieving substantial progress in the modification of magnesium-based hydrogen storage alloys. This paper systematically elaborates on major modification techniques such as alloying, nanostructuring, and catalytic material doping, providing a comprehensive analysis of the strengths and limitations of each approach. Furthermore, it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.