Development and Challenges of Metal Hydrides in Solid-State Hydrogen Storage: Dynamics, Stability, and Combustion

As a clean and efficient secondary energy, hydrogen energy is a key path to solving global energy shortage and environmental problems. Solid-state hydrogen storage technology has become the core support for the large-scale application of hydrogen energy due to its advantages of high safety, high hydrogen storage density and simple operation. This review focuses on typical high hydrogen storage density metal hydrides such as AlH 3 and MgH 2 , summarizing the research progress on their hydrogen storage mechanism, hydrogen release rate control, interfacial water and oxygen stability, and ignition and combustion characteristics. It is discussed that nanostructuring, catalyst doping and alloying can effectively optimize the hydrogen release kinetics of metal hydrides. At the same time, strategies such as hydrophobic modification and surface coating can synergistically improve material dynamic properties and water-oxygen stability. The combustion process of AlH 3 and MgH 2 includes multi-stage issues such as thermal decomposition, hydrogen combustion, and metal oxidation. It also analyzes the current application bottlenecks of solid-state hydrogen storage technology, looks forward to its future development trends and industrialization prospects, and provides theoretical reference and new insights for the advancement of industrialization of solidstate hydrogen storage technology.