Sol-Gel Preparation of Nanoscale TiO2/SiO2 Composite for Eliminating of Con Red Azo Dye

Abstract

A new anatase/SiO2 nanocomposite was synthesized by sol-gel method at room temperature using titanium tetrachloride and tetraethylorthosilicate as raw materials. Characterization of the product was carried out by means of X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) specific surface areas, Thermogravimetry analysis (TGA), Fourier transform infrared (FT-IR), and UV-vis absorption spectroscopy. Thermal phase transformation studies of composite were carried out up to 1100°C which showed the establishment of anatase TiO2 phase. The presence of some tetrahedral coordination of TiO2 species in SiO2 matrix was confirmed by UV-Vis study. The produced TiO2/SiO2 nanocomposite has good photocatalytic properties due to its anatase phase, existence of tetrahedral coordination of TiO2 in the SiO2 matrix and very large surface area. Furthermore, the synthesized anatase/SiO2 shows significant adsorption ability towards Congo Red (CR) azo dye in comparison with the pure commercial TiO2 which is known as Degussa, P25.