Visible light activated sulfur and iron co-doped TiO2 photocatalyst for the photocatalytic degradation of phenol

FeS codoped TiO2 photocatalysts were prepared by a sol–gel process and low-temperature solvothermal method. The obtained samples were characterized by XRD, UV–vis DRS, FT-IR, BET, EPR and XPS. Compared with undoped TiO2 and S doped TiO2 photocatalysts, the FeS codoped TiO2 photocatalysts exhibited much higher photocatalytic activity for phenol degradation under visible light irradiation. The optimal ratio of Fe/Ti is 1.0 at%. It was revealed that the band gap of FeS codoped TiO2 was obviously decreased, extending the light response of TiO2 into visible light region, and sulfate ions were absorbed on the surface of the TiO2. The high visible light photocatalytic activity of TiO2 was assigned to the beneficial co-effects between S and Fe. The doped Fe(III) and SO42− anchored on TiO2 surface are favorable for the separation of photo-induced electrons and holes, suppressing the recombination of electrons and holes and consequently promoting the formation of hydroxyl radical.

The beneficial co-effects between S doping and Fe(III) doping can largely decrease the band gap energy due to the formation of impurity levels and suppress the recombination of electrons and holes by trapping electrons, leading to higher photo activity of FeS codoped TiO2 than that of undoped and S-doped TiO2.Figure optionsDownload high-quality image (139 K)Download as PowerPoint slideHighlights
► FeS codoped TiO2 photocatalysts were prepared by a facile low-temperature solvothermal method.
► The FeS codoped TiO2 photocatalysts have excellent photocatalytic activity of phenol degradation.
► S and Fe(III) codoping can largely decrease the band gap energy of TiO2, extending the absorption in visible light area.
► The high photocatalytic activity for phenol was caused by the co-effects between S doping and Fe(III) doping.