Reusable CNTs-based chemical sensors

Recovery time, which is one of the key metrics in gauging sensor performance, is crucial for CNTs sensors since it directly affects the reusability, reliability and accuracy of the sensors during detection. Using the resistive f-CNTs based ethanol vapor sensor as an example, we proved that the annealing method of heating up the sensor with a sufficient high current for a certain time period can effectively facilitate the sensor return to its original status. During experiments, chemical sensors, batch fabricated by forming bundles of chemically functionalized multi-walled carbon nanotubes along the Au electrodes on SiO2/Si substrates using dielectrophoresis technique, were developed for ethanol vapor detection. In addition, experiments were carried out to determine the relationship between recovery time and other parameters during ethanol vapor detection, such as annealing current, exposure time, and ethanol vapor concentration.