Carbon-supported TiN composites serve as catalysts to enhance the (de)hydrogenation kinetics of MgH2

Hydrogen storage materials are the primary solution for addressing safety concerns in hydrogen energy storage and transportation. Despite the advantages of magnesium-based hydrogen storage materials, such as high capacity and good reversibility, their poor kinetic performances severely limit their practical applications. In this study, the synthesis of titanium nitride supported on carbon (TiN@C) was achieved through a controllable hydrothermal method, aiming to enhance the hydrogen storage performances of MgH2.With the catalytic action of TiN@C, MgH2 could rapidly release over 6.0 wt% of hydrogen at 300 °C within 15 min, while the onset dehydrogenation temperature decreased to 226 °C. The dehydrogenated MgH2 could reabsorb 5.80 wt% of hydrogen at 200 °C for 15 min with a reduced activation energy of 44.9 kJ·mol−1, demonstrating excellent kinetic performance. Mechanism analysis revealed that the multiphase interface between MgH2(Mg) and TiN@C significantly improved the hydrogen desorption kinetics of materials, especially TiN and the in-situ formed TiH2 were the main reasons for improving the hydrogen storage performance of materials.