Visible-light-driven CO2 photoreduction over atomically strained indium sites in ambient air

Strain engineering offers an attractive strategy for improving intrinsic catalytic performance of a heterogeneous catalyst. Herein, we successfully create strain into layered indium sulfide (In2S3) at atomic scale via introducing oxygen coordination and sulfur vacancy using a wet-chemistry method. The atomically strained In2S3 exhibits greatly enhanced CO2 photoreduction performance, achieving a CO2 to CO conversion rate of 5.16 μmol gcatalyst−1 h−1 under visible light illumination in ambient air. In-situ spectroscopic measurements together with theoretical calculations indicate that the atomically strained In2S3 features lattice disordered defects on surface, which provides rich uncoordinated catalytic sites and induces structural distortion, resulting in modified band structure that promotes CO2 adsorption/activation and boosts photogenerated charge carriers’ separation during CO2 photoreduction. This work provides a new approach for the rational design of atomically strained photocatalysts for CO2 reduction in ambient air.