DRS showed that there were obvious absorption edges around 400 nm for the two specimens and TiO2 nanotubes had an absorption edge blue shifted compared with the TiO2 film.

• 紫外可见漫反射吸收光谱表明两个样品在400nm左右都有明显的吸收带边，但TiO_2纳米管的吸收带边与TiO_2膜相比具有明显的蓝移；