In order to utilize visible light in photocatalytic conversion of NOx, Fe atoms were doped in commercially available photocatalytic TiO2 powders by impregnating method. The crystal phase of TiO2 was not changed after calcination process. Analysis by both X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) indicated that Fe atoms were incorporated in TiO2 as Ti-O-Fe linkages. One significant shift of the absorption edge to a lower energy and a higher absorption in the visible light region were observed. The Fe-doped TiO2 powder exhibited photocatalytic activity for the degradation of NOx under visible light irradiation. The sample mixed with 0.2 at% Fe3+and calcined at 600 ℃ showed the best photocatalytic activity.
