Bismuth-induced oxygen vacancies on CuO/Cu2O nanospheres for selective and active electrchemical CO2 reduction to C2H4

Abstract

The construction of oxygen vacancies and heterostructures has been demonstrated to be a viable approach to improve the performance of Cu-based electrocatalysts in the CO₂ reduction reaction (CO₂RR). However, integrating these two benefits into a metal oxide-based electrocatalyst to realize synergistic effects presents a significant technological challenge. In this investigation, a novel self-sacrificing template in conjunction with a Bi doping strategy was adopted to optimize the electronic configuration of the Cu-based electrocatalyst. The experimental findings indicated that the optimal catalyst Bi-Cu_xO-3 possess rich oxygen vacancy and CuO/Cu₂O heterostructure have been obtained. Benefit from these structure characters, the adsorptive and activate ability of CO₂ on the catalyst surface have been enhanced. Additionally, the DFT calculations provide further confirmation of the promotive beneficial of oxygen vacancies and framework Bi. As anticipated, in the electrocatalytic CO₂RR test, Bi-Cu_xO-3 present the highest faraday efficiency with 50.95 % for ethylene generation and greatly stability with 60 h. This work provides some new insights into modified Cu-based electrocatalyst to improve its CO₂RR activity.