The gas sensing properties at room temperature of TiO2 nanotubes by anodization

TiO2 nanotubes were used to prepare gas sensor and the gas sensing properties to various gases were tested. Titania nanotube arrays were fabricated via anodization process in glycerol electrolytes containing NH4F.The diameter of the nanotube TiO2 was controlled by changing anodizing voltage. Results showed TiO2 nanotube gas sensors responses to ethanol and ammonia at room temperature regardless of the diameter of the nanotube. This effect can be explained by the fact that nanotubes behave as nanochannels for gas diffusion.