Ethanol sensing characteristics of ambient temperature sonochemically synthesized ZnO nanotubes

ZnO nanotubes were synthesized by a sonochemical method at low temperature. The length and the diameter of the obtained nanotubes were 1.5–2 μm and 250 nm, respectively, and the walls were about 30 nm in thickness. The sensors fabricated from the nanotubes exhibited excellent ethanol sensing properties at a working temperature of 300 °C. The nanotubes can detect ethanol vapor with concentration down to 1 ppm and also showed good sensing characteristics at relatively low temperature. Our results demonstrated that the ZnO nanotubes were very promising for gas sensors with good sensing characteristics.