Sol-Gel Synthesis of TiO2 from TiOSO4 (Part 2): Kinetics and Photocatalytic Efficiency of Methylene Blue Degradation Under UV Irradiation

The sol-gel process was used to create titanium dioxide (TiO2) nanoparticles, a nanocrystalline semiconductor. How several synthesis factors, such as titanium precursor concentration, annealing temperature, and peptization temperature, affected the structural and morphological properties of TiO2 nanoparticles were thoroughly explored. X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), measurements of the specific surface area and pore size using the BET method, and UV-visible diffuse reflectance spectroscopy were all used in this investigation. The specific surface area determined by BET analysis decreased with increasing calcination temperature. The XRD analysis showed that a composite sample consisting mainly of anatase with minor brookite phases was obtained when the titanium precursor concentration ranged between 0.2 and 0.4 M, whereas a concentration of 0.5 M resulted in the formation of pure anatase. The photocatalytic activity of the synthesized TiO2 powders under different operational parameters was evaluated for the common commercial textile dye, i.e., methylene blue (MB). It was experimented that the model pollutant decoloration follows the Langmuir-Hinshelwood (L-H) model. In view of this detailed research work, it was observed that the TiO2 produced with a titanium precursor concentration of 0.3 M, a pH value of 5 during the peptization step, and an annealing temperature of 600 degrees C were found to be the best conditions for this catalytic degradation process. When used in conjunction with a TiO2 concentration of 0.04 g/L and a reactor suspension pH value of 6.0, the TiO2 catalyst produced a stunning 98% degradation of methylene blue under these circumstances.