Preparation and characterization of silver and indium vanadate co-doped TiO_2 thin films as visible-light-activated photocatalyst

摘要

Novel visible-light-activated photocatalytic Ag/InVO_4-TiO_2 thin films were developed in this paper through a sol-gel method from the TiO_2 sol containing Ag and InVO_4.The photocatalytic activities of Ag/mVO_4-TiO_2 thin films were investigated based on the oxidation decomposition of methyl orange in aqueous solution.The Ag/InVO_4-TiO_2 thin films were characterized by X-Ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM),X-ray photoelectron spectroscopy(XPS)and UV-vis absorption spectroscopy(UV-vis).The results revealed that the Ag/InVO_4-TiO_2 thin films extended the light absorption spectrum toward the visible region;the Ag and InVO_4 co-doped thin films significantly enhanced the methyl orange photodegradation under visible light irradiation.It has been confirmed that the Ag/InVO_4-TiO_2 thin films could be excited by visible light(E<3.2 eV).The significant enhancement in the Ag/InVO_4-TiO_2 photo activity under visible light irradiation can be ascribed to the simultaneous effects of doped noble metal Ag by acting as electron traps and InVO_4 as narrow band gap sensitizer.