Preparation of single-walled carbon nanotube/TiO2 hybrid atmospheric gas sensor operated at ambient temperature

Single-walled carbon nanotubes (SWCNTs)/TiO2 hybrid gas sensors operated at a room temperature were fabricated. SWCNTs were stabilized on a Si substrate with interdigitated Pt-electrodes to prepare a gas sensor. Sensing properties of the gas sensor were measured in various concentrations of NO gas. Resistance of the prepared SWCNT based gas sensor decreased with increase of NO gas concentration due to electron transfer from p-type SWCNTs to NO molecules. The SWCNT gas sensor showed high sensitivity and rapid response to the test gas. The hybrid gas sensor using SWCNTs doped with anatase TiO2 nano-particles was developed, which could work at room temperature under UV-LED (lambda=377 nm) irradiation. It showed rapid recovery to the initial state and higher sensitivity than the SWCNT gas sensor due to TiO2 photocatalytic effect. (c) 2008 Elsevier B.V. All rights reserved.