Properties and research progress of magnesium based hydrogen storage materials

Magnesium based hydrogen storage materials have the advantages of high hydrogen storage capacity, low price, and abundant magnesium resources in nature, and thus are considered as the most promising solid hydrogen storage materials. Due to the good stability of MgH2, the high enthalpy of hydrogen desorption (75kJ/mol H2), the high dissociation energy of hydrogen molecules on the surface of Mg and the slow diffusion rate of hydrogen atoms in the magnesium lattice, the absorption and desorption of hydrogen are stable in thermodynamics but the kinetics is slow, which limits its application in hydrogen storage. Many research achievements have been made to improve the properties of magnesium based hydrogen storage materials and this paper reviews these research reports, and summarizes the modification methods with the focuses on the effects of alloying, nanocrystallization and catalyst addition on the optimization and improvement of the thermodynamic and kinetic properties, and the mechanism of hydrogen absorption and desorption. Finally, the development prospects in this field are prospected. Based on the existing analysis, it is concluded that catalyst addition and nano modification should be comprehensively used to regulate the thermodynamic properties of MgH2 system in the future research obtain the Mg/MgH2 hydrogen storage system with high capacity and high performance, which could meet the requirements of commercial applications. © 2023 Chemical Industry Press. All rights reserved.