Poly(m-aminobenzene sulfonic acid) functionalized single-walled carbon nanotubes based gas sensor

Abstract

We have demonstrated a NH3, NO2 and water vapour sensor based on poly(m-aminobenzene sulfonic acid) functionalized single-walled carbon nanotube (SWNT–PABS) networks. The SWNT–PABS based sensors were fabricated by simple dispersion of SWNT–PABS on top of pre-fabricated gold electrodes. SWNT–PABS sensors showed excellent sensitivity with ppbv level detection limits (i.e., 100 ppbv for NH3 and 20 ppbv for NO2) at room temperature. The response time was short and the response was totally reversible. The sensitivity could be tuned by adjusting the sensor initial resistance. The sensors were also suitable for monitoring relative humidity in air.