Cu/N-codoped TiO2 prepared by the sol-gel method for phenanthrene removal under visible light irradiation

Cu/N-codoped TiO2 nanoparticles were prepared by the modified sol-gel method, to study its efficiency for the removing of polyaromatic hydrocarbon (phenanthrene) from an aqueous solution. Urea and copper sulfate pentahydrate were used as sources of doping element for Cu/N-codoped TiO2, respectively. The characterizations of the nanoparticles were done by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectra. XRD revealed that all the nanoparticles were indexed to the anatase phase structure, with crystallite size range from 11 to 30 nm, which decreased with the doping of copper and nitrogen. The photocatalytic activities of Cu/N-codoped TiO2 showed the highest activities than other TiO2 nanoparticles (TiO2 and N-doped TiO2). The photodegradation efficiency of Cu/N-codoped TiO2 on phenanthrene under visible light irradiation was slightly higher (96%) comparing to UV light irradiation (94%). Cu/N-codoped TiO2 was found to be very efficient and economical for phenanthrene removal, because the smallest amount of Cu/N-codoped TiO2 exhibited the best removal efficiency on phenanthrene.