Recent progress in transition metal nitride-based electrocatalysts for the hydrogen evolution reaction

conversion by nitrogen sources, and plasma-assisted nitridation. The HER performance of TMNs can be further enhanced through multiple strategies, including phase engineering, vacancy engineering, heteroatom doping, heterostructure engineering, and morphology engineering. These strategies are effective in optimizing the adsorption intensity of HER intermediates, facilitating HER kinetics, enhancing the density of active sites, and tuning the surface chemical properties. Despite their notable potential, current research on TMN-based HER electrocatalysts is limited by several challenges, such as insufficient in-depth investigations into their catalytic mechanisms, inadequate stability under certain conditions, and difficulties in scalable and cost-effective synthesis. Future research should focus on deepening the understanding of structure-activity relationships, improving stability under different conditions, and refining fabrication methods to narrow the performance and cost gap with commercial catalysts.