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Photodeposition is widely adopted for implanting metal/metal oxide cocatalysts on semiconductors.However,it is prerequisite that the photon energy should be sufficient to excite the host semiconductor.Here,we report a lower-energy irradiation powered deposition strategy for implanting CrOx cocatalyst on TiO2.Excitingly,CrOx-400 implanted under visible-light irradiation significantly promotes the CH4 evolu-tion rate on TiO2 to 8.4 μmol g-1 h-1 with selectivity of 98% from photocatalytic CO2 reduction,which is 15 times of that on CrOx-200 implanted under UV-visible-light irradiation.Moreover,CrOx-400 is identified to be composed of higher valence Cr species compared to CrOx-200.This valence states regulation of Cr species is indicated to provide more active sites for CO2 adsorption/activation and to modulate the reac-tion mechanism from single Cr site to Cr-Cr dual sites,thus endowing the superior CH4 production.This work demonstrates an alternative strategy for constructing efficient metal oxides cocatalysts on wide bandgap semiconductor.