Photocatalytic Properties of Nd and C Codoped TiO₂with the Whole Range of Visible Light Absorption

The Nd and C codoped TiO 2 (Nd-C-TiO 2 ) samples were successfully prepared by a facile calcination assisted solvothermal reaction without any addition of other C precursors except for Ti source and ethanol solvent. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectrum (DRS), and photoluminescence spectra (PL). The results showed that the visible absorption of as-prepared samples has been dramatically improved by codoping of C and Nd in TiO 2, which covered the UV and whole visible light range from 200 to 900 nm. Moreover, the Nd-C-TiO 2 samples represented not only excellent destruction ability of NO x gas but also degradation activity for methyl orange solution under visible light superior to pure TiO 2, C-TiO 2, and Nd-TiO 2 . The optimal Nd codoping concentration was determined as 2 at. %.