Copper doping and oxygen vacancy synergistic modification of zinc oxide nanosheets: Significantly improved antibacterial properties

In this study, copper-doped zinc oxide nanocomposites were prepared, and the oxygen vacancy was regulated by sodium borohydride. The structure of the materials was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Transmission electron microscope (TEM), Inductively coupled plasma mass spectrometry (ICP-MS) and Electron paramagnetic resonance (EPR). The photocatalytic efficiency of the 5 % Cu-doped ZnO sample (denoted as Cu-ZnO-R) was evaluated by testing its ability to kill gram-negative Escherichia coli and gram-positive Staphylococcus aureus. The results showed that 5 % Cu-ZnO-R could completely kill the target bacteria with a concentration of 2 × 107 CFU/mL within 20 min under light. EPR indicates that ·OH and ·O2− are the primary active oxygen components in photocatalytic reaction system.