Features of the resistive response to ozone of semiconductor PdO sensors operating in thermomodulation mode

Abstract

This work is dedicated to the issue of increasing the selectivity of semiconductor PdO sensors in case of ozone detection. Thin PdO films were obtained using thermal sputtering of Pd and its subsequent oxidation. We characterised the obtained material using X-ray diffraction analysis and optical spectroscopy. We studied the gas-sensing properties of thin films in the mode of periodically changing temperature. The use of the thermal modulation mode allowed discovering the extremes of the resistive response of the PdO sensor in ozone, which helped to increase the selectivity of the sensor while detecting this gas. We suggested a possible mechanism of ozone chemisorption, which determined the specific form of the thermally modulated PdO response. The studies of the resistive response of PdO sensors under the conditions of ultraviolet illumination confirmed the suggested mechanism of ozone chemisorption