Effect of Nitrogen Doping on the Photocatalytic Properties of TiO2

Abstract A series of nitrogen‐doped TiO 2 were prepared through a simple sol‐solvothermal method. The catalysts were characterized by BET, XRD, SEM‐EDS, Raman, XPS, FTIR, UV‐Vis, etc. The results show that N−TiO 2 photocatalyst has a larger specific surface area, stable anatase phase, and narrow forbidden band energy (3.17–3.24 eV). The N‐doped TiO 2 has more oxygen vacancies (OVs) than pure TiO 2 , as confirmed by results such as XPS and ESR. The photocatalytic evaluation results show that the decolorization of methyl orange reached 99.03 % over the 3 % N‐doped TiO 2 , which is 40 % higher than that of pure TiO 2 . Meanwhile, 3 % N‐doped TiO 2 exhibited a faster MO mineralisation rate than TiO 2 . After repeatedly used for 5 times, the photocatalyst 3‐N−TiO 2 still showed high activity in the degradation of MO. The improvement of the visible light performance of the N−TiO 2 photocatalyst could be attributed to the introduction of N in TiO 2 to generate new N 2p energy levels and rich OVs.