Acetone gas sensors composed of carbon nanotubes with adsorbed Au nanoparticles on plastic substrate

Carbon nanotubes (CNTs) have been demonstrated to be one of the most interesting materials for gas sensing. This study applies a simple method for the direct transfer of high-density CNTs from a SiO₂/Si substrate to a flexible substrate for acetone gas sensing at room temperature. The flexible gas sensor exhibited high sensitivities of 4.63% at room temperature for ambient acetone 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.