An S-scheme heterojunction constructed from α-Fe2O3 and In-doped carbon nitride for high-efficiency CO2 photoreduction

Abstract

The conversion of CO₂ to chemicals and fuels by photocatalysis provides a promising strategy to solve both energy crisis and environmental problems, for which the development of high-activity photocatalysts is of particular importance. Herein, an S-scheme α-Fe₂O₃/In–CN heterojunction was constructed by combining α-Fe₂O₃ nanoparticles with In-doped polymeric carbon nitride nanosheets, exhibiting excellent photocatalytic activity for CO₂ reduction. Without any sacrificial agent and cocatalyst, the production rate of CO reaches 24.3 μmol g⁻¹ h⁻¹ with up to 94% CO selectivity. The construction of the S-scheme heterojunction promotes the charge separation and the light absorption of polymeric carbon nitride (PCN). The incorporation of In atoms in the framework of PCN enhances the CO₂ adsorption and extends the lifetime of photogenerated charges. This work provides a new strategy for the design of high-performance photocatalytic materials.