Carbon nanotubes (CNTs) have been demonstrated to be one of the most interesting materials for gas sensing. This paper applies a simple method for the direct transfer of high-density CNTs from a SiO2/Si substrate to a flexible substrate for carbon dioxide (CO2), ammonia (NH3), and isopropyl alcohol gas sensing at room temperature. The flexible gas sensor exhibited high sensitivities of 4.8%, 5.4%, and 5.2% at room temperature for ambient CO2, NH3, and isopropyl alcohol gas concentrations of 800 ppm, respectively. In addition, the gas response of the CNT-based chemiresistor is attributed to p-type conductivity in the Au-modified semiconducting CNTs. Very good repeatability of the sensor response to gas concentration is demonstrated, representing a major step toward the low-cost large-scale production of this class of device.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering