A novel synthetic approach for the preparation of sulfated titania with enhanced photocatalytic activity

Abstract

A novel approach was used to synthesize sulfated titania (TiO₂) nanoparticles using 15% titanium trichloride and thiophene, in the presence and absence of oxalic acid. The catalyst structure has been characterized by using a combination of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), UV-visible diffused reflectance spectroscopy (DRS), transmission electron microscopy (TEM), cyclic voltammetry analysis (CV), BET surface area analysis, Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR). X-ray powder diffractometry showed that the catalysts are composed of only an anatase phase. DRS revealed that the sulfur doped titania catalysts showed a red shift of optical absorption. The results of both XRD and TEM revealed a decrease in the size of the sulfated titania particles. XPS provides conclusive evidence for Ti–O–S bond formation. The performance of the synthesized nanomaterial was evaluated as a photocatalyst to degrade 2,7-dichlorofluorescein dye in aqueous solution under UV light. Synthesized sulfated titania photocatalysts were found to be better than undoped and commercial titania.