CO sensing mechanism of LaCoO3

Porous LaCoO3 films with a thickness of similar to 5 mu m were printed on Al2O3 ceramic substrates by means of screen printing, and the CO gas sensing properties of the LaCoO3 thick films were characterized in the CO concentration range of 0.01%-1% and the temperature range of 200 to 600 degrees C. Sensors based on LaCoO3 films displayed high response, excellent recovery and good stability to CO gas; the sensor response to 1% CO was 49.23 at 600 degrees C, and 7.83 at a temperature as low as 200 degrees C. According to the DRIFT spectroscopy investigation, the CO sensing is a thermally activated surface oxidation process. (C) 2015 Elsevier B.V. All rights reserved.