SnO2-Modified Two-Dimensional CuO for Enhanced Electrochemical Reduction of CO2 to C2H4

Electrochemical reduction of CO 2 was a widespread method for CO 2 conversion into valuable chemical fuel. C 2 H 4 is an important product from CO 2 reduction. However, conversion of CO 2 into the hydrocarbon C 2 H 4 faced large energy barriers. Herein, we, for the first time, achieve a high efficiency for electrochemical conversion of CO 2 to C 2 H 4 on a tin-modified CuO. By modifying with Sn, we obtained a related low onset potential of C 2 H 4 as positive as −0.8 V versus RHE and a high Faradaic efficiency of C 2 H 4 as high as 22% at −1.0 V ( vs RHE). According to density functional calculation, the Sn dopant mainly enriched the electron density of CuO, while it was electron-poor in the Sn dopants. The rate of CO 2 reduction can be enhanced on Cu nanosheets with higher electron density. We believed that this work would promote the development of two-dimensional catalysts for CO 2 conversion and deepen the understanding of doping on CO 2 reduction.