Surface Defect Engineered Nano‐Cu/TiO₂ Photocatalysts for Hydrogen Production

Abstract Surface defects engineered nano‐Cu/TiO₂ photocatalysts are synthesized through an easy and cost‐effective microwave‐assisted hydrothermal synthesis, mixing commercial P25 titania (TiO₂) and oxalic acid (Ox), followed by 2.0 wt% Cu co‐catalyst (labeled as Cu_2.0) loading through in situ photodeposition during reaction. The hydrothermal treatment does not affect the catalyst crystalline structure, morphology, nor the surface area. However, depending on the Ox/TiO₂ molar ratio used an influence on the optical properties and on the reactivity of the system is detected. The presence of surface defects leads to intraband states formation between valence band and conduction band of bare titania, inducing an important enhancement in the photoactivity. Thus, Cu_2.0/gOx/P25 200 (where g is the weight of Ox and 200 the temperature in Celsius degrees used during the synthesis) have been successfully tested as efficient photocatalysts for hydrogen production through methanol (MeOH) reforming under UV light in a MeOH/ H₂O solution (10% v/v) by fluxing the system with N₂, showing an increased reactivity compared to the bare Cu_2.0/P25 system.