Atomically Dispersed Au-Assisted C–C Coupling on Red Phosphorus for CO₂ Photoreduction to C₂H₆

Abstract

Single-atom catalysts have exhibited great potential in the photocatalytic conversion of CO2 to C2 products, but generation of gaseous multi-carbon hydrocarbon products is still challenging. Previously, supports of a single atom consist of multiple elements, making C–C coupling difficult because the coordination environment of single-atom sites is diversified and difficult to control. Here, we steer C–C coupling by implanting an Au single atom on the red phosphorus (Au1/RP), support with uniform structure composed of a single element, lower electronegativity, and better ability to absorb CO2. The electron-rich phosphorus atoms near the Au single atoms can function as active sites for CO2 activation. The Au single atom can effectively reduce the energy barrier of C–C coupling, boosting the reaction kinetics of the formation of C2H6. Notably, the C2H6 selectivity and turnover frequency of Au1/RP reach 96% and 7.39 h–1 without a sacrificial agent, respectively, which almost represents the best photocatalyst for C2 chemical synthesis to date. This research will provide new ideas for the design of high-efficiency photocatalysts for CO2 conversion to C2 products.