Doping of Vanadium into Bismuth Oxide Nanoparticles for Electrocatalytic CO₂ Reduction

Electrocatalytic reduction of carbon dioxide (CO2) to formate is an effective solution to address the continuous increase in CO2 in the atmosphere. Here, we report a vanadium-doped (V-doped) bismuth oxide (Bi2O3) electrocatalyst synthesized using a facile one-step hydrothermal method for highly efficient electrochemical reduction of CO2 to formate. The doping of V can tune the intrinsic crystal and electronic structure of Bi2O3, that is, causing partial amorphization in the Bi2O3 nanosheet and decreasing electron density around Bi active sites. The partial amorphous region can provide more reactive sites; meanwhile, the electron-deficient environment around Bi enhances the adsorption of CO2. The synergistic crystal and electronic structure modulation in the V-doped Bi2O3 provides excellent electrocatalytic CO2RR performance with a high formate selectivity of 94.2% and a high partial current density of 45.03 mA cm–2 at −1.1 V (vs RHE).