Sn$^{4+}$-doped TiO$_2$ nanorod array film with enhanced visible light photocatalytic activity

[摘要] Sn$^{4+}$-doped TiO$_2$ nanorod array film (NAF) on the fluorine-doped tin oxide (FTO) conducting glass was successfully synthesized using the facile hydrothermal method. The NAF photocatalysts were characterized by the scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV–Vis diffuse reflectance spectra (DRS). The SEM images showed that both doped and pure TiO2 NAFs exhibited a good nanorod array structure. Sn$^{4+}$-doped TiO$_2$ NAF still maintains rutile crystal structure, which was identical to that of pure TiO$_2$ sample. By means of the DRS measurement, it was found thatthe Sn$^{4+}$ doping in TiO$_2$ nanorod could induce an obvious enhancement of visible light absorption owing to the introduction of doping energy level in the band gap of TiO$_2$. The degradation of methyl orange (MO) demonstrated that the Sn$^{4+}$-doped TiO$_2$ NAF exhibited an enhanced photocatalytic activity than pure TiO$_2$ NAF under the visible light ($\lambda> 400$ nm) irradiation,which should be attributed to the enhanced visible light response and improved separation efficiency of photogenerated carriers of Sn$^{4+}$-doped TiO$_2$.

[学科分类] 材料工程

[关键词] TiO$_2$ film;nanorod array;Sn$^{4+}$;ion doping;photocatalyst.