Generating oxygen vacancies in Cu2+ -doped TiO2 hollow spheres for enhanced photocatalytic activity and antimicrobial activity

Developing cheap photocatalysts with highly visible-light activity is greatly desired for environmental pollution treatment. In this work, the authors designed and synthesised Cu 2+ -doped TiO 2 (Cu-TiO 2 ) hollow spheres with enhanced photocatalytic activity and antimicrobial activity using a simple hydrothermal process. The X-ray powder diffraction (XRD) results revealed that Cu-TiO 2 hollow spheres were anatase crystal phase. The Cu 2+ -doped into TiO 2 can be confirmed by XRD, Raman spectra, and UV–Vis spectrum. The photocatalytic activity of Cu-TiO 2 samples was evaluated by the degradation of methyl orange. Comparing to the undoped TiO 2 , 6% Cu-TiO 2 sample exhibited remarkably high photocatalytic towards methyl orange under simulated sunlight irradiation, which was attributed to the fact that copper ion doping produced numerous oxygen vacancies (V O ) in the material. In addition, it also showed improved antibacterial properties against both Gram-positive Staphylococcus aureus ( S.aureus ) and Gram-negative Escherichia coli ( E.coli ) bacteria. These results establish that Cu 2+ doping can obviously improve the photocatalytic performance of TiO 2 under simulated sunlight.