Study of the characteristics, properties and characterization of new SiO₂/TiO₂/Sb₂O₅ ternary oxide obtained by the sol–gel process

SiO₂/TiO₂/Sb₂O₅ ternary oxide was prepared by the sol–gel method in two different proportions, and were characterized by X-ray fluorescence (XRF), analysis of the specific surface area by BET and the average pore size and pore volume by BJH method, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and electron dispersive spectroscopy (EDS) analyses, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and other spectroscopic technics (FT-Raman, FT-IR, UV–Vis–NIR and DRS). The ternary oxides showed high surface area 758 and 529 m² g⁻¹ for SiTiSb-A and SiTiSb-B, respectively. The binding energy values for the Sb 3d and Ti 2p levels show the insertion of Sb and Ti atoms in the silica matrix, confirming the high dispersion of the metals presented in SEM, both in the bulk and on the surface. The thermogravimetric analysis (TGA) showed weight loss of 23% for both ternary oxides. The crystallographic data showed an increase of the crystalline order with the increase of the temperature of the thermal treatment. The anatase phase as well as a small content of the rutile phase of TiO₂ were identified by FT-Raman. The Raman spectrum corroborated with the DTA and XRD of the SiTiSb-B which showed a slight decrease in the degree of crystallinity. Optical band gap values are dependent on the content of oxides. The pyridine adsorption studies showed the presence of Lewis and Brønsted acid sites on the SiTiSb ternary oxide surface, where the SiTiSb-B presented more acid sites on the surface.