Boosted Efficiency of Fe₂O₃ for Photocatalytic CO₂ Reduction via Engineering Fe−O−Ti Bonding

Abstract

Visible light‐driven photocatalytic CO2 reduction (CO2RR) offers a sustainable and promising solution to environmental and energy challenges. However, the design of efficient photocatalysts is hindered by poor interface interactions in heterojunctions and a limited understanding of reaction kinetics. A modified Fe2O3 photocatalyst, M‐Fe2O3@MXene, is introduced featuring KH‐550‐modified M‐Fe2O3 hollow nanocubes coated with MXene, constructed via an electrostatic and Fe−O−Ti bonding self‐assembly method. This design achieves an unprecedented CO production rate of 240 µmol g⁻¹ h⁻¹ among non‐noble metal catalysts (8.6 folds vs Fe2O3). The Fe−O−Ti sites enhance *COOH intermediate formation and CO production through higher electron deficiency of Fe3+ and rapid charge transfer. This study offers new insights on the use of functional metal oxides and high‐quality Mxene layers to design efficient metal oxide‐based photocatalysts.