Based On Ionic Liquid / Toner Conductivity Type Gas Sensors

With the rapid development of modern economy and technology, electronic noses have broad application prospects in the military,environmental monitoring,industrial and agricultural production control,medical and food inspection and many other fields. Carbon black/polymer composite material as a gas sensor for volatile organic vapor detection has been studied extensively. In addition, our group has also reported the gas sensors with ionic liquid as a new kind of sensitive material. In this thesis, the ionic liquid/carbon black gels were used as sensing material to fabricate the gas sensor and sensor array. Combined with chemometric data analysis method the gas sensor and senor array are used for qualitative and quantitative analysis of the organic vapors. Some preliminary results are obtained as following:1) The thermal stability and morphology of carbon black-ionic liquid gel were studied by using scanning electron microscopy and thermal gravimetric analysis, respectively. Results suggested that the gels are homogeneous and show a high stability.2) The gas sensors based on the carbon black-ionic liquid gel were fabricated. The sensor showed a good stability and reproductility. The response signal of the gas sensor at different temperature suggested that the gel is both the electron conductor and the ionic conductor.3) A three unit gas sensor array based on different ionic liquids were fabricated. Combined with principal component analysis (PCA), the sensor array were successfully used for five different kinds of organic vapors'discrimination.4) The BmimPF6/carbon blackgel showed different affinity toward the ethanol molecular and the water molecular. Thus, combined with the artificial neural network method, a BmimPF6/carbon black gel gas sensor can be used for quantitative analysis of ethanol-water mixed vapors.