Mechanically induced Cu active sites for selective C-C coupling in CO2 electroreduction

Developing a convenient method to endow bulk Cu-based electrode with high activity of electrocatalytic CO2 reduction reaction (CO2RR) to multicarbon (C2+) products is desirable but challenging. Herein, for the first time, we report that mechanical polishing induces highly reactive Cu sites for selective C-C coupling in CO2RR. We find that mechanical polishing could endow Cu foil with abundant nanocavity surface structure, which efficiently confines the carbonaceous intermediates to enhance the probability of C-C coupling reaction. By confining the carbonaceous intermediates with Cu nanocavity, the as-prepared electrode delivers a Faradaic efficiency toward C2+ products of 65.7 % at-1.3 V vs. RHE, which is enhanced up to 1.7 folds compared with that of commercial Cu foil. This work provides a new method to enable Cu foil with high activity of CO2RR to C2+ products. (c) 2022 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

This study reports the use of mechanical polishing to create abundant nanocavities on Cu electrode surface, which effectively confines the carbonaceous intermediates and enhances the probability of C-C coupling reaction in CO2RR. The prepared electrode exhibits a high Faradaic efficiency for C2+ products at negative potentials.