Tailoring Oxygen Vacancies with Atomically Dispersed Cu Sites for Stable and Efficient Photothermal CO2 Conversion

Abstract

Photothermal catalysis under mild conditions represents a promising and sustainable approach for CO₂ conversion into high-value chemicals, thereby enabling efficient carbon recycling. However, precise manipulation of active sites and their coordination environments at the atomic level to enhance catalyst performance still remains a challenge. Here, we present a single-atom doping strategy for oxygen vacancy engineering to facilitate efficient CO₂ conversion. Specifically, an In₂O₃-based catalyst with abundant oxygen vacancies induced by homogeneously dispersed Cu single atoms is constructed, exhibiting a competent CO₂ reduction performance in photothermal reverse water-gas shift reaction. The optimal Cu-In₂O₃ catalyst achieves a CO yield rate of 46.17 mol g_Cu⁻¹ h⁻¹ with near-unity selectivity (>99%) and demonstrates stability over 450 h under 3 W cm⁻² full-spectrum light illumination. Comprehensive spectroscopic characterization and computational simulations elucidate that the Cu single atoms synergistically interact with oxygen vacancies to promote H₂ dissociation and CO₂ activation under photoexcitation. This work provides insights into the design of photothermal catalysts, emphasizing the transformative potential of atomic-site engineering for efficient CO₂ conversion and sustainable energy technologies.