Magnesium hydride (MgH₂) is a promising solid-state hydrogen storage material due to its high hydrogen content and cyclic stability. However, its practical applications are limited by slow desorption kinetics and a high dehydrogenation temperature. To address these challenges, Pt-loaded MAX fibers with oxygen vacancies (Pt@MFs) have been synthesized by using vortex and hydrothermal methods. And the effects of the Pt@MFs on the hydrogen storage properties of MgH₂ are investigated. The results display that the MgH₂ doped with 10wt% Pt@MFs begins dehydrogenation at 169.3 ℃ and absorbs 5.73 wt% hydrogen in just 30 s at 125 ℃ and 30 bar hydrogen pressure. After 30 cycles, the MgH₂–10 wt% Pt@MFs retains 98.7% of its initial capacity, showcasing excellent cycling stability. The synergistic effect of the MAX fiber network’s active sites, oxygen vacancies, anchored Pt nanoparticles and intermetallic compounds (PtTi, Pt₃Ti) in the MgH₂–10 wt% Pt@MFs composite significantly enhances hydrogen storage kinetics by facilitating diffusion, optimizing electron transfer, and weakening Mg-H bonds. The design concept of this material offers a novel strategy for improving the kinetics and stability of MgH₂.

Developing efficient catalysts is pivotal for advancing MgH₂-based hydrogen storage systems. In this study, a novel catalyst, graphene oxide-supported oxygen vacancy-rich Co₃O₄ and Ni nanoparticles (Ni-O_V-C@GO), was synthesized to enhance the hydrogen storage performance of MgH₂. The catalyst dramatically improved the kinetics of MgH₂, lowering the initial hydrogen desorption temperature of Ni-O_V-C@GO-MgH₂–7 to 438 K, which is 386 K lower than that of as-milled MgH₂. The composite achieved 5.0 wt% hydrogen absorption at 423 K within 600 s and retained 97.3 % capacity after 30 cycles. Notably, the activation energy for H₂ desorption was reduced to 40.78 kJ/mol, an 80 % decrease compared to pristine MgH₂. The in-situ formation of CoMg₂/CoMg₂H₅ and Mg₂Ni/Mg₂NiH₄ acted as “hydrogen pumps”, facilitating multiple hydrogen transfer pathways. Additionally, oxygen vacancies elongated Mg-H bonds, enhancing dehydrogenation kinetics through catalytic effects. These findings provide valuable insights into improving hydrogen adsorption and desorption kinetics in MgH₂-based systems.