Confined Cavity on a Mass-Producible Wrinkle Film Promotes the Selective CO2 Reduction
Reduction of CO2 into carbon monoxide (CO) is the starting point for producing valuable carbon chemicals and liquid fuels. To date, efficient CO2 electroreduction to CO has been accomplished predominantly by the control of the structural parameters of a catalyst, including its nanostructure and surface morphology. In this study, the highly selective CO formation (~90% of faradaic efficiency) at a low applied potential (-0.4 V vs. reverse hydrogen electrode) was reported by the control of the local pH near the reaction site, which was of less interest compared to other factors. The local pH near the reaction site was controlled by a confined cavity in the Au wrinkle film. Experimental and computational calculation results revealed that such enhancement is mainly related to the few-micrometer-amplitude confined space in the tens-nanometer-thickness Au wrinkle film. Notably, the fabrication of the wrinkle catalyst film was extremely simple, permitting large-scale fabrication.