Effect of Ce, N and S multi-doping on the photocatalytic activity of TiO2

•Doping with multiple ions (Ce, N, S) enhances the photocatalytic activity of TiO2.•In the multi-doped TiO2, S substituted for Ti whereas N substituted for O.•Lifetime of the photogenerated charge carriers is higher in the doped samples.•Improved visible light absorption occurs as a result of multi doping.•Synergistic effect of the dopants is responsible for the enhanced photocatalytic activity. A visible light active photocatalyst was synthesized by multiple doping of TiO2 with Ce, N and S. The multidoped catalyst showed higher photocatalytic activity for methyl orange degradation from aqueous solution compared to P25 and undoped TiO2. The photocatalytic activity decreased in the order Ce0.6NS–TiO2>P25>NS–TiO2>Ce0.6–TiO2>TiO2. TiO2 and doped TiO2 existed as anatase phase with average particle size of 10nm. In the multidoped TiO2, N substituted for O whereas S substituted for Ti. UV–vis absorption spectra showed an increased visible light absorption for doped TiO2 compared to the undoped one. An increased fluorescence lifetime for the charge carriers was observed for the doped samples as compared to undoped TiO2. The enhanced photocatalytic activity of Ce0.6NS–TiO2 is attributed to a synergistic effect of the dopants in increasing the visible light absorption and lifetime of the photogenerated charge carriers.