Tin-oxide nanotubes for gas sensor application fabricated using SWNTs as a template.

We develop a simple method to synthesize nano tube or wire structure of tin-oxide for gas sensor application. It is realized by the rheotaxial growth and thermal oxidation (RGTO) of tin on porous single-wall carbon nanotubes (SWNTs) as a template. The morphology and chemical property of thus formed nanostructures are examined. The electrical and NO(x) gas sensing properties are also investigated. The sensor exhibits a fast response time of less than 100 seconds and a good recovery. A sensing response of 23,400% to 10 ppm concentration at 200 degrees C is observed.