Relationship between the Catalytic and Detection Properties of SnO and Pt/SnO Systems

Semiconductor gas sensors based on metal oxides have been widely accepted as an important tool for the detection of different gases in air. An understanding of all the mechanisms related to such detection is essential in order to improve the sensitivity and selectivity of these gas detectors. This paper considers the mechanism of detection by semiconductor oxide gas sensors in terms of catalytic reactions described by Rideal–Eley and Langmuir–Hinshelwood mechanisms. Some relationships were discussed between the catalytic and detection properties of SnO 2 and Pt/SnO 2 systems used on the one hand as catalysts of low-temperature CO oxidation and on the other hand as sensors of CO in air.