Temperature dependence of gas sensitivities on a catalytic thin film

Abstract

Catalytic detectors [l] are used in coal mines for methane measurement. A catalytic platinum thin film has been developed in collaboration between INERIS and LETI, with the aim of a large production for a low cost, and a low electric consumption partly due to a discontinuous heating. The technology has been described elsewhere [2], and response curves to methane, for different temperatures of the sensor, were established. This sensor could also be used in industries other than mining, and gases to be detected are not limited to methane. So we have studied the response of this Sensor to methane and other gases. 1 shows the response. of the thin fYm for temperatures between 600 and 1000 “C, and concentrations of methane from 0 to 60% LEL (lower explosive limit). At high temperatures, not only methane but other explosible gases are detected; see Fig. 2 showing the detection of propane, butane and hexane as well. The responses of this sensor to different gases for the same concentrations in percent LEL are not very different; these gases will be detected in the same sensitivity range,