Highly sensitive mixed oxide sensors for the detection of ethanol

Sensors consisting of mixtures of tin dioxide and zinc oxide powders in a range of proportions were constructed. Each mixture was applied to an electrode-bearing alumina substrate either as a paste, or by screen printing. The responses of these sensors, and of three commercially-available Figaro sensors, to ethanol vapour in the 1–1000 parts-per-billion (ppb) range were measured. At 100 ppb of ethanol vapour, the most sensitive paste sensor (25% SnO2/75% ZnO) exhibited a response that was more than twice that of the screen-printed sensors, and almost 60 times greater than that of the most sensitive Figaro sensor (TGS822).