Recent advances in metal-organic frameworks for solid-state hydrogen storage: Synthesis, optimization, and perspectives

Hydrogen energy is recognized as a promising secondary energy for sustainable development due to its high calorific value and environmental friendliness, yet its widespread applications are currently hindered by inefficient storage and need good storage methods to realize. Metal-Organic Frameworks (MOFs) have attracted significant attention as the promising materials for solid-state hydrogen storage (SHS) due to their high surface area, porosity, and structural tunability. A great deal of researches has demonstrated MOFs possess high hydrogen storage capacity in low-temperature and high-pressure conditions. This review provides a systematic overview of the synthesis methods of MOFs, optimization methodology, and the perspectives for future development. The synthesis methods of MOFs, including the solvothermal or hydrothermal method, microwave-assisted method, ultrasound-assisted method, electrochemical method, and mechano-chemical method, etc., were discussed and compared. Also, the optimization includes the structural design and post-synthesis modification, and they were introduced and analyzed in detail. Finally, the possible development direction of synthesis and optimization the MOFs for the future hydrogen storage practical applications was proposed. It aims to provide insights into the improvement of the hydrogen storage efficiency of MOFs, contributing to the realization of a sustainable hydrogen economy.