Theoretical and experimental study of the response of CuO gas sensor under ozone

In this paper, we assumed that the ozone detection mechanism of p-type semiconductor resistive gas sensors in dry air is essentially due to adsorption of species O-2, O-2(-), O and O- at the surface of the grains. Based on the Wolkenstein adsorption theory, a dynamic model was formulated taking into account the chemical interactions between the sensor and chemisorbed species and the conduction mechanism. The present model predicts the coverage degree and sensor response as a function of characteristic properties of the semiconductor: grain size, working temperature and ozone concentrations. The simulation results are compared with the experimental data obtained with a CuO based sensor made in our laboratory and the correlation between simulated and experiments results is quite good. (C) 2013 Elsevier B.V. All rights reserved.