Multi-wall carbon nanotube-polymethyl methacrylate composite for volatile organic compound sensor

Abstract

Development of gas sensor for detecting toxic gas was conducted in this research work. The gas sensor was fabricated from composite materials between multi-walled carbon nanotube (MWCNT) and polymethyl methacrylate (PMMA). The composite was synthesized by the in situ polymerization and fabrication of the sensor by screen-printing method. The objective of this research was to investigate the performance of MWCNT/PMMA composite as a gas sensor for detecting volatile organic compound. Furthermore, the parameters which affected the response and electrical resistance of the fabricated sensor were investigated. MWCNTs content with weight ratio of 2.0, 2.5, 3.0 and 3.5, gas concentration in a range of 500 to 1500 ppm and types of organic gas (methanol toluene acetone and cyclohexane) were experimentally investigated. The experimental results showed that the increased electrical resistance of the composite was attributed to the exposure to VOC gas, with a response time of less than 3 minutes. In addition, an increased in the MWCNTs content oppositely led to a decrease in the sensitivity of the sensors. On the other hand, the sensitivity was increased with an increased in the gas concentration. Finally, the sensitivity of sensor depended on types of chemical vapor due to interaction between gas molecule and polymer matrix.