Synthesis of WO₃–TiO₂ composite for photocatalytic and antibacterial applications under UV irradiation

This study aimed to synthesize WO₃–TiO₂ composites and investigate their chemical and physical properties using XRD, SEM, FTIR, and UV–Vis spectroscopy. In addition, the photocatalytic performance for methylene blue degradation and antibacterial activities against E. coli and S. aureus under UV light irradiation were evaluated. The band gap of TiO₂ was shifted to a lower energy, reaching 2.88 and 2.99 eV for the 1 and 5 mol% WO 3 –TiO 2 samples, respectively. The photocatalytic efficiency of the synthesized sample was compared with that of pure TiO 2 (65%), and the results showed that the 5 mol% WO₃–TiO₂ sample demonstrated the highest photocatalytic activity, with a degradation efficiency of 83%. Kinetic analysis demonstrated that the reaction rate followed a pseudo-first-order model. Antibacterial results against E. coli and S. aureus revealed a time-dependent trend, where 1 mol% WO 3 –TiO 2 showed better performance at the initial stage (1−2 h ), whereas 5 mol% WO 3 –TiO 2 was more effective at longer irradiation times (3–4 h), suggesting a two-stage antibacterial mechanism. In summary, WO 3 enhances charge separation, leading to increased photocatalytic production of reactive oxygen species (ROS, •OH and O 2 • − ) in aqueous suspension.