Synthesis and characterization of TiO 2 photocatalyst doped by transition metal ions (Fe 3+, Cr 3+ and V 5+)

Nano TiO 2 was synthesized by the hydrothermal method. The sample was doped with transition metal ions (V, Cr and Fe) and non-metal (N). Doped TiO 2 samples were characterized by x-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and UV-Vis diffuse reflectance spectroscopy (UV-Vis). Photocatalytic activity in the mineralization of xylene (vapor phase), methylene blue and active dyer PR (liquid phase) was tested. In comparison with non-doped TiO 2, V-, Cr-, Fe-doped TiO 2 and N-doped TiO 2 samples exhibited much higher photocatalytic activity using visible light instead of UV.