Theory of metal oxide gas sensors for measuring combustibles

A first principles model is described for the operation of electrochemical type sensors designed to measure combustibles in air. It is based on the same general principles as presented in previous publications [1,2] for an ab initio model developed to describe the operation of metal oxide oxygen sensors. The present model is used to analyze experimental data reported in the literature [3] and to indicate the variety of behavior expected from these sensors depending on the properties of the electrode materials. This analysis is expected to aid the design and optimization of these sensors.