Abstract: A visible-light responsible non-metal C-N-S-tertiary doped TiO2 was synthesized by a sol-gel process using Ti(OC4H9)4 and functional biology organic cystine as raw materials. The obtained photocatalysts were characterized by the means of X-ray powder diffraction(XRD), X-ray photoelectron spectroscopy(XPS), fourier transition infrared spectra(FT-IR), ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS). XRD showed that, by C, N and S tertiary-doping, the growth of TiO2 crystallite was restrained and the temperature of phase transformation from anatase to rutile of TiO2 was enhanced effectively. DRS showed the extension of light absorption edge in the range of visible-light was up to 800 nm. XPS analysis revealed that C and S existing on the surface of TiO2 photocatalyst was the state of CO2-3 and S6+, respectively. Nitrogen species could be ascribed to the form of N—Ti—O and Ti—O—N. And more hydroxyl groups were found on the C-N-S tertiary doped catalyst. The photocatalytic activities of the as-prepared photocatalysts were evaluated by degradation of Rhodamine B(RhB) in an aqueous suspension under visible light. It was found that C-N-S-tertiary doped TiO2 exhibited improved photocatalytic activity compared with that of P25 TiO2. Under the visible-light irradiation ranging from 470 to 800 nm for 2 h, an 83% removal rate of RhB could be achieved.

Key words: titanium dioxide, non-metal tridoped, visible-light, photocatalytic, Rhodamine B