Silver nanoparticle loaded TiO2 nanotubes with high photocatalytic and antibacterial activity synthesized by photoreduction method

Silver nanoparticles (Ag NPs) were loaded on TiO2 nanotubes (TNTs) via photoreduction method at room temperature without any additional reducing agent. The morphology and crystal structure were examined by transmission electron microscopy, X-ray diffraction pattern, and Raman spectroscopy. Chemical states of silver, titanium, and oxygen were analyzed by X-ray photoelectron spectroscopy. The results showed that Ag NPs with an average diameter of 5 nm were uniformly distributed on TNTs surface. Ag NPs improved both photocatalytic and the antibacterial activity of TNTs under sunlight irradiation. Ag/TNTs decomposed 81.2% of methylene blue and 75.8% of methylene orange after 150 min under sunlight irradiation. In addition, Ag/TNTs at 20 ppm concentration eliminated 99.99% of Staphylococcus aureus after 60 min under sunlight irradiation. This research demonstrated that Ag/TNTs can be synthesized at industrial scale by the photoreduction method and are effective antibacterial materials.