Photocatalytic activity of V-doped TiO 2 thin films for the degradation of methylene blue and rhodamine B dye solutions

摘要: Highly-transparent V-doped TiO2 thin films were prepared by sol-gel processing, spin coated on fused silica glass substrates, and annealed in air at 450 °C for 2 h. All of the comprised anatase as sole crystalline phase. The XPS data suggested that V formed an interstitial solid solution with anatase. formation unsaturated lowest doping level 0.05 mol% resulted lattice defect sites, which enhanced recrystallisation, grain growth, crystallinity. In contrast, supersaturated/oversaturated solutions higher levels 0.10–1.00 mol% deformation, partial amorphisation, precipitation, liquid formation. coexistence multiple valence states, viz., Ti4+/3+, V4+/3+, possibly V5+ doped was attributed to intervalence charge transfer. Dye degradation tests revealed showed best photocatalyic performance this combined effects greater crystallinity reduced band gap. increasing V-doping gradual decreases photocatalytic performance, are principally decrease areal density surface-active sites owing liquid-phase densification. MB relative RhB is cationic nature MB, allows adsorption photocatalyst surface comparison anionic RhB.