CNTs-Pd as Efficient Bidirectional Catalyst for Improving Hydrogen Absorption/Desorption Kinetics of Mg/MgH₂

Abstract

The hydrogen storage potential and cost-effectiveness of MgH 2 have rendered it a desirable material for hydrogen storage. However, its application has been hindered by limitations in thermal stability and dehydrogenation kinetics. In this study, the carbon nanotube-Pd bifunctional catalyst was prepared by using hydrothermal and calcination technology, significantly improving the kinetics of Mg/MgH 2 during hydrogen adsorption/desorption. The activation energy for the Mg@ CNTs-Pd was reduced to 42.73 kJ/mol, as determined by fitting the Avrami−Erofeev model with the Arrhenius equation. Additionally, the activation energy during dehydrogenation was found to be 73.98 kJ/mol based on the Johnson−Mehl−Avrami−Kolmogorov equation and the Arrhenius equation. It is worth noting that the dynamic enhancement persists even after 10 cycles. This groundbreaking research has paved the way for potential applications of MgH 2 as a hydrogen storage material, providing it with broader development opportunities.