Preparation and characterization of a novel activated carbon-supported N-doped visible light response photocatalyst (TiO2-xNy/AC)

A photocatalyst, TiO2-xNy/AC (activated carbon (AC) supported N-doped TiO2), highly active in both the Vis and UV range, was prepared by calcination of the TiO2 precursor prepared by acid-catalyzed hydrolysis in an ammonia atmosphere. The powders were characterized by diffuse reflectance spectroscopy, scanning electron microscopy, X-ray diffraction, N-2 adsorption, Fourier transform infrared spectroscopy and phenol degradation. The doped N in the TiO2 crystal lattice creates an electron-occupied intra-band gap allowing electron-hole pair generation under Vis irradiation (500-560 nm). The TiO2-xNy/AC exhibited high levels of activity and the same activity trends for phenol degradation under both Vis and UV irradiation: TiO2-xNy/AC calcined at 500 degrees C for 4 h exhibited the highest activity. The band-gap level newly formed by doped N can act as a center for the photo-generated holes and is beneficial for the UV activity enhancement. The performance of the prepared TiO2-xNy/AC photocatalyst revealed its practical potential in the field of solar photocatalytic degradation of aqueous contaminants. (c) 2007 Society of Chemical Industry.