The research of photocatalytic activity on Si doped TiO2 nanotubes

Pure TiO2 nanotubes (TiO2 NTs) and Si-doped TiO2 NTs (Si–TiO2 NTs) were prepared by one-step solvothermal procedure using titanium oxysulfate and tetraethoxysilane as titanium and silicon sources, respectively. The structure and morphology of the samples were characterized by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Energy Dispersive Spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS) showed that the introduction of Si into TiO2 NTs could be controlled successfully. The result of N2 absorption-desorption (BET) displayed that 5% Si–TiO2 NTs had the highest specific surface areas among all the samples. Notably, UV–Vis absorption spectra test showed that 5% Si–TiO2 NTs had a much higher photocatalytic activity compared with other samples, and exhibited a remarkable red-shift and absorption intensity appeared under UV irradiation. Therefore, the photocatalytic activity of TiO2 NTs can be greatly improved with suitable amount of Si doping.