A facile strategy to fabricate plasmonic Cu modified TiO2 nano-flower films for photocatalytic reduction of CO2 to methanol

Cu nanoparticles (NPs) deposited TiO2 nano-flower films were fabricated using a combination of a hydrothermal method and a microwave-assisted reduction process. The investigations indicated that Cu NPs and TiO2 film both exhibit visible light harvesting properties based on localized surface plasmon resonance (LSPR) of Cu NPs and unique nanostructures of TiO2 film. Fluorescence quenching was observed because the recombination of charge carriers was effectively suppressed by Cu NPs deposition. The experimental results indicate that Cu/TiO2 films exhibit better activity for the photocatalytic reduction of CO2 due to the charge transfer property and LSPR effect of Cu NPs. The CH3OH production rate reached 1.8 mu mol cm(-2) h(-1) (energy efficiency was 0.8%) over 0.5 Cu/TiO2 film under UV and visible light irradiation, which was 6.0 times higher than that observed over pure TiO2 film. In addition, a tentative photocatalytic mechanism is proposed to understand the experimental results over the Cu modified TiO2 nano-flower films. (C) 2015 Elsevier Ltd. All rights reserved.