Effect of annealing temperature on phase transition and optical property of titanate nanotubes prepared by ion exchange approach

In this paper, the effect of the annealing temperature on the phase transition and optical property of titanate nanotubes was discussed in detail. TGA results indicated that the dehydration process happened when titanate nanotubes were annealed. Up to 450 °C, the weight loss ceased entirely. XRD results showed that anatase and triclinic Ti5O9 were formed in annealed samples. TEM was used to observe the micrographs of samples. SAED patterns indicated that the granular phase and the rod-shaped crystal were triclinic Ti5O9 and anatase, respectively. In addition, UV–vis diffuse reflectance spectra were used to study the optical band gap of samples annealed at different temperature.