Pt decorated SnO2 nanoparticles for high response CO gas sensor under the low operating temperature

Gas sensors based on noble metal/metal oxide are applied extensively, and show a relatively high response to carbon monoxide at inferior operating temperature. In this paper, a carbon monoxide sensor based on Pt decorated SnO2 nanoparticles is obtained by a hydrothermal method. Abundant characterization methods are used to analyze the structure, morphology, chemical state and specific surface area of the as-prepared compounds. The pure SnO2 sensor exhibits inferior operating temperature and low response for the detection of carbon monoxide. In contrast, the observed response of the sensor with the as-synthesized 1.5 mol% Pt decorated SnO2 is up to 610.45 at a low operating temperature of 80 °C, and the response value is about three times higher than that of SnO2 sensor. The significantly improved performance is thoroughly explained in terms of the adsorption–desorption mechanism, and the chemical sensitization and electronic sensitization of Pt.