UV-Light-Induced Surface Reconstruction of Cubic Cu 2 O Promotes CO 2 Electroreduction to C 2 Products.

Carbon dioxide electroreduction has been considered as one of the most appealing ways to reducing the CO 2 emission but raising the selectivity of high-value added products like C 2+ still faces great challenge. Herein, we report a convenient way to modify the cubic Cu 2 O particles through UV-light irradiation induced reduction in a solution containing H 2 O 2 and i-propanol. The plane surface of Cu 2 O was reconstructed to roughness shell composed of abandant grain boundaries, in which the ration of Cu + /Cu 0 can be easily regulated by controlling the irradiation time. At the same time, the increasing electrochemical active surface area facilitated the exposure of active sites. Combining of above factors, the Faradaic efficiency of C 2 (ethylene and ethanol) from CO 2 electroreduction was greatly increased to 62.56% with a high partial current density of 145 mA cm -2 . Our work put forward a facile method for the fine control of the surface structure of cuprous oxide and a novel platform to elucidate the synergistic effects of Cu + /Cu 0 on CO 2 electroreduction.