Solution–Gel Method Preparation of High-Performance TiO2/GO/CdS Nanocomposites Under Ultrasonic Radiation and Research on Antibacterial Properties

To improve the visible-light response and antibacterial performance of titanium dioxide, a TiO2/GO/CdS mesoporous nanocomposite was prepared via an ultrasound-assisted sol–gel method in this study. Systematic characterizations including XRD, XPS, SEM, TEM, BET, UV-Vis DRS and FTIR were carried out to analyze the structure, morphology and optical properties of the material. The results show that the composite exhibits a typical mesoporous structure with a specific surface area of 197.0962 m2/g and a pore size distribution of 2–14 nm. CdS is successfully doped into the TiO2 matrix and forms a heterostructure with GO. UV-Vis diffuse reflectance spectra indicate that the synergistic effect of CdS and GO significantly broadens the visible-light absorption range of TiO2 and suppresses the recombination of photogenerated carriers. Antibacterial tests using Escherichia coli as the target strain demonstrate that the TiO2/GO/CdS composite exhibits remarkably better visible-light photocatalytic bactericidal activity than pure TiO2 and the TiO2/GO composite. This work provides a new strategy for the modification of TiO2-based photocatalytic antibacterial materials, and the as-prepared composite shows promising application prospects in the antibacterial field.