Three-dimensional structural ReS2@Cu2O/Cu heterojunction photocatalysts for visible-light-driven CO2 reduction

Exploring novel and efficient photocatalysts to accelerate CO 2 photoreduction into useful chemicals or fuels is of great significance. In this work, we developed the three-dimensional (3D) structural heterojunction photocatalysts composed of ReS 2 and Cu 2 O by a drop-casting approach. The ReS 2 microspheres with nanosheets were deposited on the 3D structure of Cu 2 O/Cu foams. The analysis of UV–Vis absorption and PL spectra showed that the ReS 2 @Cu 2 O/Cu heterostructure delivered enhanced visible light absorption and improved charge carrier separation. The resulting ReS 2 @Cu 2 O/Cu-180 exhibited the CO yield of 14.3 µmol g −1 under the visible light irradiation. The realized S-scheme heterostructure not only promoted the separation of the photogenerated electron and hole pairs, but also enhanced the visible light absorption. Furthermore, the enriched electrons with high reducing abilities aggregated into the conduction band and diffused to the surface of Cu 2 O for favoring the CO 2 reduction and CO formation. This study is expected to provide a strategy to prepare high-performance S-scheme photocatalysts to perform efficient photocatalytic CO 2 reduction.