Preparation and characterization of copper-doped anatase TiO2 nanoparticles with visible light photocatalytic antibacterial activity

Anatase titanium dioxide (TiO2) nanoparticles doped with copper (1.0–3.0 mole%) were synthesized by sol–gel method. The UV–visible diffused reflectance measurement revealed that the doping of the Cu2+ ions in TiO2 lattice extends its optical absorption in the visible region. XRD and XPS analysis revealed that the substitutions of the few sites of Ti4+ ions by Cu2+ ions. TEM analysis revealed the non-spherical nanoparticles size within the range 8–12 nm. The role of hydroxyl radicals during bacterial inactivation was studied by photoluminescence technique. The bactericidal activity of copper doped titanium dioxide nanoparticles was tested against pathogenic bacteria Escherichia coli and Staphylococcus aureus under visible light irradiation. The bacterial survival does not seem to be affected by in contact with nanoparticles in dark.