Preparation of V doped Co2N/CoN and its superior HER and OER performance

Hydrogen is increasingly recognized as a critical energy source for the future. Transition metal nitrides hydrogen catalysts have found to narrow the d-band contraction effectively and alter the filling state of the metal, thereby modulating the metal-hydrogen bonding energy and enhancing both electrical conductivity and catalytic activity. In this study, V-doped cobalt nitrides (V–Co 2 N/CoN) with two distinct crystalline structures were successfully synthesized through the nitriding of V-doped cobalt bicarbonate (V–CoCH) as a precursor. The morphology and structure of the resulting materials were carefully optimized by adjusting the V doping amount and nitriding temperature. For hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), the final product V–Co 2 N/CoN-1-400 only needs 47 mV and 230 mV overpotential to reach 10 mA cm −2 , and works at 1.69 V to drive the overall water splitting for 10 mA cm −2 , showing good stability performance without fluctuation for about 10 h. This work implies that V-doped cobalt nitrides can lead to enhanced water splitting catalytic activity. Our findings may illustrate the significance of V doping for improving electrocatalytic performance, and demonstrate the potential of CoV bimetallic nitrides as effective electrocatalysts , offering valuable insights for the further development of non-precious metal nitride-based catalysts.