Efficient visible light-induced degradation of phenol on N-doped anatase TiO2 with large surface area and high crystallinity

The N-doped anatase TiO2 photocatalysts were prepared via solvothermal and ethylenediamine reflux treatment, followed by the sequential calcination in air and NH3/N2 atmosphere. The resulting photocatalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and UV–vis diffuse reflectance spectra. The results revealed that the prepared N-doped anatase TiO2 had characteristics of small crystallite size, large surface area, high crystallinity and visible light response. The prepared N-doped anatase TiO2 photocatalysts showed much higher photocatalytic activity than N-doped Degussa P25 for the degradation of phenol under both ultraviolet and visible light irradiation, owing to more highly oxidizing hydroxyl radical which was the main oxidative species responsible for the degradation of phenol.