Optimizing hydrogen storage properties: MXene (MX)-VCl3 assisted kinetics in Magnesium/Magnesium hydride for sustainable energy

Abstract

Hydrogen storage in Mg/MgH₂ materials is a key study for the energy storage applications. Hydrogen storage is one of the most critical issues in developing a viable solution to the depletion of energy resources. Magnesium hydride is characterized by its kinetic equilibrium, lightweight, and cost-effectiveness, which leads to increased hydrogen densities. MgH₂ has an overall hydrogen storage of 7.6 wt%, yet only in certain circumstances is full-capacity release/storage possible. V-containing compounds are fascinating catalysts owing to their attraction for electrons due to empty d orbitals. 2D material: MXene (MX) has a large surface area, allowing for simple functionalization with numerous chemical groups, making them a choice for energy storage. In this work, a mixture of Mg-5wt% (MX + VCl₃) was produced by ball milling and tested for hydrogen storage. The hydrogen storage of Mg-5wt% (MX + VCl₃) is 2.32 wt% at 320 °C. The thermogravimetric plot shows that 200 °C is the onset temperature, 326 °C is the thermal decomposition temperature, and 397 °C is the endpoint. The weight loss for Mg-5wt% (MX + VCl₃) shows intermediate reactions and complex thermal behavior that are driven by the additives. XRD, FESEM with EDS, XPS and TEM are used to characterize the structural, morphology, chemical oxidation state and crystallinity of the samples. The activation energy for the dehydriding reaction is 126.53 kJ/mol.