Suppression of cross-sensitivity to humidity in pristine, suspended single-walled nanotube NO2 sensors

The humidity response of pristine, suspended single-walled carbon nanotube (SWNT) gas sensors is analyzed. We employ ultraclean, dry-transferred carbon nanotubes, whose surface is not exposed to any resist-based or wet-chemical processes. Thanks to this, the nanotube surface remains pristine before gas exposure. The sensor response to NO2 follows a Langmuir isotherm. No cross-sensitivity to water up to 60% R.H. is observed, and the device remains sensitive to NO2 with no apparent degradation of the response