Boosting CO2 photoreduction over perovskite quantum dots decorated with dispersed ruthenium nanoparticles

High efficiency CO2 conversion materials are ideal for solar to carbon fuel conversion. Halide perovskite quantum dots (QDs) are highly desirable as catalysts and have been extensively investigated in the field of CO2 photoreduction. The major challenge lies in the severe charge recombination and the weak ability to activate CO2. Herein, we have identified dispersed Ru nanoparticles anchored on CsPbBr3 (CPB) QDs as prospective photocatalysts for CO2 reduction at ambient pressure with light irradiation. The optimized 0.45 % CPB@Ru reduced CO2 to CO at a rate of 28.12 mu mol g- 1 h- 1 without any sacrificial agent and co-catalysts, about 4 times higher than that of the CPB QDs (7.03 mu mol g- 1 h- 1). Experiments and DFT calculations reveal that the asprepared CPB@Ru showed increased photogenerated charge separation, CO2 adsorption/activation and lower energy barriers for the formation of *COOH intermediate, which are crucial for enhancing the photocatalytic CO2 reduction activity. This work provides a convenient pathway for designing high-performance perovskite photocatalysts with high selectivity and high catalytic activity using metal nanoparticle loading technology.