Hybrid Cu2O/TiO2 Nanocomposites with Enhanced Photocatalytic Antibacterial Activity toward Acinetobacter Baumannii.

The hybrid Cu2O-TiO2 photocatalytic composite with a p-n heterojunction was synthesized by the supercritical solvothermal route. The uniformly distributed Cu2O was stably combined with TiO2 to benefit the increase of the specific surface area, the harvesting of visible light, and the separation of photogenerated holes and electrons. As a result, photocatalytic inactivation of Acinetobacter baumannii under visible-light irradiation was facilitated. Based on the photogenerated holes acting as the main active species, the Cu2O-TiO2 photocatalytic heterojunction could induce the leakage of K+ ions and serious damage of the cell structure, leading to the final cell death. During the photoantibacterial process on Cu2O-TiO2, the RecA gene played a significant role in enhancing the survival rate of Acinetobacter baumannii. Furthermore, the great bactericidal effect of Cu2O-TiO2 nanocomposites to different bacteria indicated the potential application for the environment-friendly disinfection.