Abstract：The mesoporous RGO-TiO2 thin films were synthesized by dipping-coating assisted heat treatment and ultraviolet lamp irradiation reduction with tetrabutyl titanate (TBT), natural flake graphite as raw materials and polyvinylpyrrolidone (PVP) as mesoporous template. The structure, morphology and properties of samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area (BET), UV-Vis diffuse reflectance spectra (UV-Vis DRS) and Fourier transform infrared (FTIR). The reaction property of the removal of Ni2+and SDBS by photocatalysis of mesoporous RGO-TiO2 thin films were evaluated with Ni2+ and SDBS as target pollutants. The GO amount and the effects of pH on its catalytic performance were discussed. The photocatalytic reduction of Ni2+ and photocatalytic oxidation of SDBS in Ni2+/SDBS co-existed system were further studied under the optimum condition. The results showed that the mesoporous RGO-TiO2 thin film had the highest photocatalytic efficiency for single system Ni2+ and SDBS with the content of 1.0wt% GO; The reduction efficiency of Ni2+ and the degradation efficiency of SDBS were the highest when the pH values were 7.5 and 6, respectively. In summary, the removal efficiency of Ni2+ and SDBS in the co-existed system was better than that of the single system under the additions that the amount of GO was 1.0wt% and pH≈6. The reduction rate of Ni2+ was 87.9% and the oxidation rate of SDBS was 95.5%. In this present contribution, the mechanism of synergistic photocatalysis was further explored. It can be concluded that the Ni2+ synchronous reduction occured by the photogenerated electrons and the oxidation producted CO2·- free radical when the TiO2-SDBS surface complex was oxidized under the excitation of ultraviolet light.
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