Calorimetric detection of volatile organic compounds

A calorimetric sensor arrangement was developed to detect volatile organic compounds. The heat power which is generated by the sorption or desorption of the vapor at a receptor layer and which is converted into a voltage signal by silicon thermopile chips was used as input parameter for the multicomponent analysis. If the design and operation conditions have been properly adjusted, calorimetric sensors are useful for measurements in the lower ppm range as the reported results show. In order to demonstrate the improvement of the discrimination power of an electronic nose by incorporating calorimetric sensors, the developed sensor arrangement was adapted to the electronic nose MOSES II. According to the calculated Mahalanobis distance, the improvement of the discrimination power by combination with other types of sensors depends on the nature of the samples. In some cases, best results were obtained with combinations including the calorimetric sensors.