Optimizing the Structural and Photocatalytic Properties of TiO₂ Composites Synthesized via Sol-Gel Method

Abstract

Titanium dioxide (TiO₂) is widely studied for its photocatalytic and optical properties, but its performance can be enhanced by forming composites with other materials. This research focuses on synthesizing TiO₂ composites using the sol-gel technique by incorporating Al₂O₃, WO₃, ZnO, CNT, and SiNT. Additionally, optimizing the calcination process by modifying time and temperature is crucial to improving structural and functional characteristics. TiO₂ composites were synthesized via the sol-gel method, followed by controlled calcination under varying temperature and time conditions. X-ray diffraction (XRD) was employed to analyze the crystalline phases, while surface area and porosity were examined to assess material properties. UV-Visible spectroscopy was used to study the absorption spectra and band structure alterations in the composites. XRD analysis confirmed that the TiO₂-Al₂O₃ composite contained both anatase and rutile phases, along with Al₂O₃, exhibiting a specific surface area of 32.1 m²/g and an average crystallite size of 18.09 nm. The TiO₂-WO₃ composite demonstrated the formation of a mixed oxide system at the interface, altering its electronic properties. Optical absorption spectra revealed significant modifications in band structures, affecting light absorption and photocatalytic efficiency. The structural and optical characteristics of TiO₂ composites were significantly influenced by the choice of secondary material and calcination conditions. The findings suggest that optimizing these parameters can enhance photocatalytic performance, making TiO₂ composites promising for applications in environmental remediation and materials science.