Vanadium-Regulated Ultrafine Molybdenum Carbide Nanoparticles by Anchorage on Graphene for Highly Active Hydrogen Evolution Reaction

Platinum-like molybdenum carbide (Mo2C) coupled with carbon-based supports is an effective strategy to promote the performance of catalysis and energy storage. However, inevitable aggregation of Mo2C impede the achievement of high catalytic performance for hydrogen evolution reaction (HER). Herein, a vanadium-doped Mo2C nanoparticles anchorage on graphene (V-Mo2C) was developed. The V atoms can effectively regulate the electronic structure of Mo2C, improving the intrinsic activity and kinetics of electrocatalyst for HER. The ultrafine Mo2C nanoparticles with the size of about 2 nm are firmly anchorage on conductivity graphene substrate, which increases the number of active sites and contributes the high HER activity. As results, the V-Mo2C nanocomposite exhibits a remarkable HER performance with overpotentials of 284 mV at -10 mAand#183;cm-2 and corresponding Tafel slopes of 65.0 dec-1 in 1M KOH. Notable, the V-Mo2C hybrid is observed long term stability for andgt; 24 h, demonstrating that the structure of Mo2C nanoparticles anchored on graphene can significantly improve the performance for HER as well as stability. This work provides a reference for the synthesis of high-performance ultrafine transition metal carbide for HER or other catalytic system.