Nitrogen and vanadium Co-doped TiO 2 mesosponge layers for enhancement in visible photocatalytic activity

Novel N and V co-doped TiO 2 mesosponge (N-V-TMSW) layers were successfully prepared by one-step hydrothermal treatment of TiO 2 nanotube arrays, and the phase composition, morphology and optical property were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and UV–vis diffusion reflectance spectroscopy (DRS). The crystal structure and density of states were studied by means of the first-principle pseudo-potential plane wave. The results indicated that titanium ions and oxygen atoms in TiO 2 were successfully substituted by vanadium ions and nitrogen atoms, respectively. The sample N-V0.1-TMSW showed a remarkable absorption in the visible light range of 400–600 nm and high visible photocatalytic activity