Enhanced electrochemical performance with Co-V-O bridges and dual active sites for water electrolysis applications

Abstract

Vanadium pentoxide (V₂O₅) exhibits broad application prospects in the field of battery cathode materials due to its layered structure and high theoretical specific capacity. However, its inherent low electrical conductivity and structural instability during cycling severely restrict its electrochemical performance. To overcome these bottlenecks, cobalt (Co)-doped V₂O₅ materials were successfully prepared via a hydrothermal synthesis method in this study. Characterization confirmed that Co ions were successfully incorporated into the V₂O₅ lattice, which effectively expanded the interlayer spacing and improved the electronic conductivity of the material. Electrochemical test results showed that compared with pure V₂O₅, the Co-V₂O₅ sample demonstrated excellent hydrogen evolution reaction and oxygen evolution reaction performances, with lower overpotentials and Tafel slopes. As a catalyst for driving water electrolysis, the sample exhibited a cell voltage of 1.38 V at 10 mA cm⁻² and excellent long-cycle stability.