Double-shelled plasmonic Ag-TiO2 hollow spheres toward visible light-active photocatalytic conversion of CO2 into solar fuel

Double-shelled hollow hybrid spheres consisting of plasmonic Ag and TiO2 nanoparticles were successfully synthesized through a simple reaction process. The analysis reveals that Ag nanoparticles were dispersed uniformly in the TiO2 nanoparticle shell. The plasmonic Ag-TiO2 hollow sphere proves to greatly enhance the photocatalytic activity toward reduction of CO2 into renewable hydrocarbon fuel (CH4) in the presence of water vapor under visible-light irradiation. The possible formation mechanism of the hollow sphere and related plasmon-enhanced photocatalytic performance were also briefly discussed.