Constructing Core-Shell Co@N-Rich Carbon Additives Toward Enhanced Hydrogen Storage Performance of Magnesium Hydride

Magnesium hydride (MgH₂) is regarded as a promising solid-state hydrogen storage material, on account of its moderate price and high gravimetric capacity. However, MgH₂'s inferior kinetic of hydrogen release impedes its widespread application. In this work, we use core-shell Co@N-rich carbon (CoNC) additive as catalysts to ameliorate the performances of MgH₂. The surface morphologic structures and hydrogen desorption kinetics of different MgH₂-CoNC composites are systematically studied. We find that MgH₂-5 wt% CoNC with carbon contents of 17% (CoNC0) composites exhibit better hydrogen desorption performance. At 325°C, the MgH₂-5 wt% CoNC0 composites can release up to 6.58 wt% of H₂ in 5 min, which is much higher than 0.3 wt% for pure MgH₂. Our results demonstrate that importing the core-shell structured catalysts can effectively enhance the hydrogen release kinetics.