Enhanced Photocatalytic Activity of TiO₂ Modified with GaI toward Environmental Application

Gallium (Ga) ion-doped TiO₂ (Ga-TiO₂) nanocomposite with small particle size (9-10 nm) and high surface area (104 m²/g) has been easily synthesized via sol-gel method at low temperature by using low-valent GaI as a doping precursor. The structural and morphological characterization of Ga-TiO₂ was carried out with standard analytical and spectroscopic techniques. Ga doping into the TiO₂ matrix inhibited a phase transformation from anatase to rutile (photocatalytically inactive) form, even at a higher temperature of 750 °C. Finally, Ga-TiO₂ nanocomposite showed high photocatalytic activity and exhibited 97% degradation of acid violet 63 dye within 60 min. The dye degradation rate constant was calculated as 1.6 × 10^-1 and 1.4 × 10^-1 min^-1 under UV and white light irradiation, respectively, which is higher, as compared to the previously reported Ga-TiO₂ composites to date.