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.