Selectivity of amperometric gas sensors in multicomponent gas mixtures

In recent years smog and poor air quality became a growing environmental problem. There is a need to continuously monitor the quality of air. The lack of selectivity is one of the most important problems limiting the use of gas sensors for this purpose. In this study, a selectivity of the six amperometric gas sensors is being investigated. Calibration of sensors has been performed in order to find a correlation between concentration level and sensor output. The responses of each sensor to the concentrations from 50 ppb to 1 ppm of selected gases have been measured. Usually, sensors responses are measured only in the presence of one gas. The main goal was to study different interactions between sensors and gases in multicomponent gas mixtures. Sensors were studied under controlled conditions, a constant gas flow rate of 100 mL/min and 50 % relative humidity.