Simultaneous CO2 and H2O Activation via Integrated Cu Single Atom and N Vacancy Dual-Site for Enhanced CO Photo-Production

Photocatalytic conversion of CO2 into fuels using pure water as the proton source is of immense potential in simultaneously addressing the climate-change crisis and realizing a carbon-neutral economy. Single-atom photocatalysts with tunable local atomic configurations and unique electronic properties have exhibited outstanding catalytic performance in the past decade. However, given their single-site features they are usually only amenable to activations involving single molecules. For CO2 photoreduction entailing complex activation and dissociation process, designing multiple active sites on a photocatalyst for both CO2 reduction and H2O dissociation simultaneously is still a daunting challenge. Herein, it is precisely construct Cu single-atom centers and two-coordinated N vacancies as dual active sites on CN (Cu-1/N2CV-CN). Experimental and theoretical results show that Cu single-atom centers promote CO2 chemisorption and activation via accumulating photogenerated electrons, and the N2CV sites enhance the dissociation of H2O, thereby facilitating the conversion from COO* to COOH*. Benefiting from the dual-functional sites, the Cu-1/N2CV-CN exhibits a high selectivity (98.50%) and decent CO production rate of 11.12 mu mol g(-1) h(-1). An ingenious atomic-level design provides a platform for precisely integrating the modified catalyst with the deterministic identification of the electronic property during CO2 photoreduction process.