Abstract

TiO_2 nanopowders with anatase structure were firstly prepared by controlling the pH value of a precursor solution without any heat-treatment at room temperature. The prepared TiO_2 nanopowders were hydrothermally treated in 10M NaOH solution at 170°C. Then, the samples were washed in DI water or 0.1M HCl. The TiO_2 nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The gas sensitivity of TiO_2 nanotubes for toluene gas was also investigated. The results show that TiO_2 nanotubes can be prepared by hydrothermal treatment. The morphology of TiO_2 nanotubes prepared by 0.1M HCl washing is destroyed to some extent. TiO_2 nanotubes with DI water washing show better sensitivity than that with 0.1M HCl washing.

• Keywords: TiO_2 nanotubes;Hydrothermal treatment;Gas sensitivity;Toluene gas;