Distinction of gaseous mixtures based on different cyclic temperature modulations

The dynamic nonlinear response of a SnO2 semiconductor gas sensor under two types of temperature modulations was investigated to enhance the selectivity of the sensor for gaseous mixtures. A “rapid increase and slow decrease” and “slow increase and rapid decrease” in temperature scan were periodically applied to the SnO2 semiconductor gas sensor. The resultant dynamic change in the conductance of the sensor was characteristically changed depending on the gases and the combination of the mixture. The gaseous mixtures were partly possible to distinguish by the three types of classification based on the sum of the individual sensor responses and the selective response to a specific gas.