ZnIn₂S₄/ZnO Film for High-Efficiency CO₂Conversion to Fuel: Photocatalysis by Atomically Disorder-Engineered Heterointerface

Light-driven conversion of CO₂into small energy-rich molecules effectively addresses both energy demands and reduction in carbon dioxide emissions. However, due to the low efficiency of light absorption and charge carrier separation/transfer, most semiconducting materials have a low conversion activity and poor conversion product selectivity. Herein, ZnIn₂S₄nanosheets are introduced to oxygen vacancy-rich ZnO microrod films for CO₂conversion. This heterostructure forms an atomically disordered heterointerface that can play an important role in strengthening the contact between the two crystalline materials and providing an efficient charge transfer pathway. The resulting ZnIn₂S₄/ZnO film photocatalyst exhibits superior performance compared to other ZnO-film-based photocatalysts (0.84 and 0.34 μmol·cm^–2·h^–1for CH₄and CO, respectively) with ∼90.8% selectivity toward CH₄production. The formation of the ZnIn₂S₄/ZnO heterojunction film contributes to strengthening the charge carrier generation, separation, and migration through a defect-engineered Z-scheme mechanism. This work highlights the role of disorder-engineered heterointerfaces in film-based heterostructured photocatalysts for optimizing the CO₂conversion efficiency.