Cu-doped TiO2 nanoparticles for photocatalytic disinfection of bacteria under visible light

Two percent Cu-doped TiO2 nanoparticles were prepared by a modified ammonia-evaporation-induced synthetic method, calcined at 450 °C, and characterized by powder X-ray diffraction, energy dispersive X-ray analysis, ESR spectroscopy, scanning electron microscopy, UV–visible diffuse reflectance spectrum, photoluminescence spectroscopy, and electrochemical impedance spectroscopy. Doping shifts the optical absorption edge to the visible region but increases the charge-transfer resistance and decreases the capacitance. Under visible light, the composite nanoparticles very efficiently catalyze the disinfection of Escherichia coli. The prepared oxide is selective in photocatalysis; under UV light, its photocatalytic activity to degrade sunset yellow, rhodamine B, and methylene blue dyes is less than that of the undoped one.

Graphical abstractTwo percent Cu-doped TiO2 nanoparticles, prepared by a modified ammonia-evaporation-induced synthetic method, efficiently catalyze disinfection of E. coli under visible light. Figure optionsDownload full-size imageDownload high-quality image (104 K)Download as PowerPoint slideResearch highlights► Doping TiO2 with Cu by a modified ammonia-evaporation-induced synthetic method shifts the absorption edge to the visible region. ► Cu–TiO2 nanoparticles catalyze bacteria disinfection under sunlight. ► Cu–TiO2 is selective in photocatalysis.