Defect in reduced graphene oxide tailored selectivity of photocatalytic CO2 reduction on Cs4PbBr6 pervoskite hole-in-microdisk structure

Artificial photocatalytic conversion of CO2 into value-added and renewable fuels has been recognized as a promising approach for solving environmental problems and energy crisis. Achieving this goal, developing a photocatalyst to simultaneously manifest high efficiency, selectivity, and durability is urgent need. Herein, one of all-inorganic cesium lead halide perovskite (viz. Cs4PbBr6) with hole-in-microdisk structure hybridized with reduced graphene oxide (rGO) is reported as an effective photocatalyst for reducing of CO2. Our results show that Cs4PbBr6/rGO exhibited high efficiency, selectivity, and durability of CO2 reduction capacity to CO, catalyzing at a rate of 11.4 μmol g-1h-1 with a maintaining stability of 60 h. Residual oxygen impurities as defects in the rGO sheets are demonstrated for facilitating CO2 activation and reduction capacity to CO. This finding provides a facile pathway for designing high performance perovskite photocatalyst with high selectivity and durability with the aid of defects engineering. Taking advantage of all-inorganic perovskite (Cs4PbBr6) and residual oxygen defects in reduced graphene oxide, high efficiency, selectivity and durability of CO2 reduction capacity to CO is successfully achieved. [Display omitted] •Cs4PbBr6 perovskite with hole-in-microdisk (HIMD) structure hybridized with reduced graphene oxide is synthesized.•HIMD Cs4PbBr6/rGO acts as an effective photocatalyst for CO2 photoreduction.•Defects in rGO sheets are demonstrated for improving the activity and selectivity of CO2 photoreduction.