Study on the effect of coconut shell charcoal doping on the hydrogen storage performance of Mg-based materials

Mg-based hydrogen storage materials possess high hydrogen storage capacity and abundant resource availability, but their practical application is limited by high reaction temperatures, slow kinetics, and poor cycling stability. In this study, coconut shell charcoal was incorporated into Mg-based hydrogen storage alloys through mechanical ball milling to improve their overall hydrogen storage performance. The effects of carbon addition were investigated using hydrogen absorption kinetics, pressure-composition-temperature measurements, X-ray diffraction, and scanning electron microscopy. Results show that coconut shell charcoal significantly improves hydrogen absorption kinetics, lowers plateau pressure, and shortens reaction time. Moreover, the carbon-supported structure suppresses particle agglomeration and structural degradation during cycling, enhancing stability. This work demonstrates the potential of biomass carbon materials as effective modifiers for improving the comprehensive hydrogen storage performance of Mg-based materials.