Visible-light-driven CO 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 (InS) at atomic scale via introducing oxygen coordination and sulfur vacancy using a wet-chemistry method. The atomically strained InS exhibits greatly enhanced CO photoreduction performance, achieving a CO to CO conversion rate of 5.16 μmol g h under visible light illumination in ambient air. In-situ spectroscopic measurements together with theoretical calculations indicate that the atomically strained InS features lattice disordered defects on surface, which provides rich uncoordinated catalytic sites and induces structural distortion, resulting in modified band structure that promotes CO adsorption/activation and boosts photogenerated charge carriers' separation during CO photoreduction. This work provides a new approach for the rational design of atomically strained photocatalysts for CO reduction in ambient air.