Cu2O/Reduced Graphene Oxide Composites for the Photocatalytic Conversion of CO2

Abstract

A facile one‐step microwave‐assisted chemical method has been successfully used for the synthesis of Cu 2 O/reduced graphene oxide (RGO) composites. Photocatalytic CO 2 reduction was then investigated on the junction under ambient conditions. The RGO coating dramatically increases Cu 2 O activity for CO 2 photoreduction to result in a nearly six times higher activity than the optimized Cu 2 O and 50 times higher activity than the Cu 2 O/RuOx junction in the 20 th hour. Furthermore, an apparent initial quantum yield of approximately 0.34 % at 400 nm has been achieved by the Cu 2 O/RGO junction for CO 2 photoreduction. The photocurrent of the junction is nearly double that of the blank Cu 2 O photocathode. The improved activity together with the enhanced stability of Cu 2 O is attributed to the efficient charge separation and transfer to RGO as well as the protection function of RGO, which was proved by XRD, SEM, TEM, X‐ray photoelectron spectroscopy, photo‐electrochemical, photoluminescence, and impedance characterizations. This study further presents useful information for other photocatalyst modification for efficient CO 2 reduction without the need for a noble‐metal co‐catalyst.