The gas sensing properties of TiO2 nanotubes synthesized by hydrothermal method

In this paper, the TiO2 nanotubes were synthesized by hydrothermal method using a 10 mol/L NaOH aqueous solution at 150 °C. The structure of prepared materials was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM) and Brunauer–Emmett–Teller (BET). The prepared TiO2 nanotubes were used to prepare thick film gas sensors and the gas sensing properties to various gases were tested. Results show the prepared TiO2 nanotube gas sensors responses to ethanol under dry condition at 450 °C. This could be attributed to the fact that it had high porous morphology and a higher pore volume, which can promote the diffusion of ethanol deep inside the films and improve the sensor response. Moreover, the gas sensor made with nanotubes exhibit high selective response towards ethanol gas compared with H2, CO, acetone.