The Preparation of N-doped Titanium Dioxide by Metallothermic Reduction Method and Their Photocatalytic Activity

N-doped titanium dioxide (TiO2) particles were prepared by metallothermic reduction (MTR) method and their photocatalytic activities under UV and visible light irradiation were investigated. The mixture composed of anatase-type TiO2, Mg and NaN3 was calcined at 600°C in nitrogen atmosphere for 1 hour. Although two types of TiO2 particles, with low and high crystallinity, were used as starting materials, both obtained particles kept anatase-type crystalline and XPS spectra of them had peaks assigned to Ti-N bond. The absorption onset of the particles prepared from TiO2 with low crystallinity shifted significantly from UV region to visible one. This N-doped TiO2 particles had photocatalytic activity against oxidative degradation of gaseous 2-propanol even under visible light (>440 nm) irradiation.