Study on preparation and antibacterial property of Cu/TiO2 composite nanoparticles

Cu/TiO₂ composite nanoparticles were prepared by photoreduction deposition methods. The properties of the nanoparticles were widely characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) equipped with energy dispersive X-ray spectroscopy (EDS). Moreover, the antibacterial performances were performed by zone of inhibition (ZOI) tests against the bacteria species. The results suggested that the pH value had great influence on the properties of Cu/TiO₂ composite nanoparticles. Cu element tends to exist as Cu₂O when the pH is high, but Cu element does as pure Cu phase when pH value is low. With the increase of UV irradiation time, Cu phases are subsequently oxidized to Cu₂O, and the amount of Cu₂O in composite nanoparticles increased. The antibacterial activities of composite nanoparticles against Staphylococcus aureus are well and enhanced with the increase of the Cu₂O amount. The synergistic effect was found between Cu and TiO₂.