Synergistic Co-N/V-N dual sites in N-doped Co 3 V 2 O 8 nanosheets: pioneering high-efficiency bifunctional electrolysis for high-current water splitting

Developing affluent dual-metal active sites bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is essential to achieve large-scale water electrolysis, whereas still remains challenging. Herein, a novel nitrogen-doped cobalt-vanadium oxide with abundant Co-N and V-N dual active sites supported on nickel foam (N-Co V O @NF) is constructed by a controllable impregnation-thermal nitridation strategy. The staggered nanosheet structure ensures optimal exposure of active sites. More importantly, N doping effectively regulates the electronic structure of the metal centers and induces the formation of Co-N and V-N dual active sites, which is conducive to improving the conductivity and hydrophilicity, thus synergistically enhancing the electrocatalytic efficiency. Consequently, the optimized N-Co V O @NF exhibits prominent HER (63 mV@10 mA cm ) and OER (256 mV@10 mA cm ) activities, surpassing most contemporary bifunctional electrocatalysts. In practical application, the assembled N-Co V O @NF electrolyzer consistently achieved ultra-low cell voltages of 1.97 and 2.03 V at 500 and 1000 mA cm , respectively, superior to the benchmark RuO @NF || Pt/C@NF and showcasing robust durability. This paves the way for its prospective adoption in industrial water electrolysis applications.