Environmental temperature-independent gas sensor array based on polymer composite

This paper reports the effect of gas temperature on the response of sensor array based on polymer-carbon black composite. Temperature-controlled chemical vapors of chloroform, methanol, benzene, acetone, and cyclohexane were injected into the sensor array equipped with a micro heater. The temperature of the sample gas was varied (20, 40, and 60 °C) and the resistance change was measured with the sensor films thermostatted at the temperature of 25 and 45 °C, using embedded micro heater. The maximum relative differential resistance of polymer composite was severely affected by the gas temperature, and the response pattern of the sensor array also changed with the gas temperature. Consequently, the chemical vapors controlled at the temperature of 20 and 40 °C were recognized differently in principal component space, even though the same concentration of chemical vapor was injected. However, when the polymer detector was maintained at a temperature of 45 °C, radial-response patterns for the gas temperature of 20 and 40 °C showed similar shape and were recognized identically in the projected principal component space.