Abstract We fabricated Sn-doped TiO2 nanotubular film via annealing of anodized TiO2 nanotubes grown on F–SnO2 (FTO) glass. Annealing was carried out at 500 °C in ambient air. Anatase crystal structure was achieved with no change in nanotubular morphology in respect to as-anodized amorphous TiO2 nanotubes. The X-ray photoelectron spectroscopy analysis revealed Sn on the surface of TiO2 film, following the thermal treatment, probably caused by the diffusion from FTO glass. Depth profile examination of the film chemical composition was conducted by elastic recoil detection analysis, which showed that in addition to the diffusion of Sn from FTO, diffusion of Ti to FTO concurrently occurred. Thus, a higher concentration of Sn was found at the bottom of the tubes, while a lower concentration was present on the tubes’ surface top. This explains the improved optical response revealed by a diffuse reflectance spectroscopy. The absorption enhancement demonstrated that Sn-doped TiO2 film was efficient in the degradation of methyl orange dye under visible light.

中文翻译：

---

Sn掺杂TiO2纳米管薄膜光催化降解甲基橙染料

摘要 我们通过对生长在 F-SnO2 (FTO) 玻璃上的阳极氧化 TiO2 纳米管进行退火制备了 Sn 掺杂的 TiO2 纳米管状薄膜。退火在 500 °C 的环境空气中进行。相对于阳极氧化的无定形 TiO2 纳米管，锐钛矿晶体结构没有改变纳米管形态。X 射线光电子能谱分析表明，热处理后 TiO2 薄膜表面有 Sn，这可能是由 FTO 玻璃扩散引起的。通过弹性反冲检测分析对薄膜化学成分进行了深度剖面检查，结果表明除了 Sn 从 FTO 扩散外，还同时发生了 Ti 向 FTO 的扩散。因此，在管底部发现较高浓度的锡，而在管表面顶部存在较低浓度。这解释了漫反射光谱所揭示的改进的光学响应。吸收增强表明Sn掺杂的TiO2薄膜在可见光下对甲基橙染料的降解是有效的。