Improvement of Mg-Based Hydrogen Storage Materials by Metal Catalysts: Review and Summary

Abstract

Magnesium hydride (MgH₂) has become a very promising hydrogen storage material because of its high hydrogen storage capacity, good reversibility and low cost. However, high thermodynamic stability and slow kinetic performance of MgH₂ limit its practical application. In the past few decades, many alternative methods have been designed to solve this problem. A large number of studies have demonstrated that the use of metal catalyst doping modification, MgH₂ nanocrystallization and other methods can greatly improve the hydrogen absorption and dehydrogenation performance of MgH₂. Therefore, this paper reviews and summarizes the modification effect of transition metal catalyst doping on the hydrogen storage performance of MgH₂, especially the catalysis on the de/rehydrogenation performance of MgH₂. In addition, promoting effects of carbon materials, transition metal alloys and compounds on the hydrogen storage performance of MgH₂ were also summarized. Finally, the existing problems and challenges of MgH₂ as hydrogen storage materials are discussed, and some possible strategies are proposed.