Multi-electron storage of photoenergy using Cu 2O–TiO 2 thin film photocatalyst

Abstract

UV–vis irradiation of thin films of TiO 2 (ITO/TiO 2) and Cu 2O/TiO 2 (ITO/Cu 2O/TiO 2) coated on conducting glasses generate H 2 from H 2O and once the illumination is ceased, the H 2 production was still noticeable under dark for ITO/Cu 2O/TiO 2 at a lesser production rate for up to 2 h. No such dark reactions were observed for ITO/TiO 2 or TiO 2-coated copper metal foil (Cu/TiO 2). It was noticed that the irradiation of ITO/Cu 2O/TiO 2 leads to formation of trapped electrons and this stored energy leads to generate H 2 from H 2O in the dark.