Mixed Potential Hydrocarbon Sensors based on a YSZ Electrolyte and Oxide Electrodes

The mixed potential response of perovskite-type oxide electrodes on a yttria stabilized zirconia (YSZ) electrolyte have been examined. The effects of varying the electrode and electrolyte composition and morphology on the sensor response have been studied in detail. was found to be an excellent electrode material for a highly selective nonmethane hydrocarbon sensor. Moreover, the sensor response was greatly improved by decreasing the heterogeneous catalysis on the YSZ electrolyte. Optimizing the electrode and electrolytes resulted in a sensor response of up to 100 mV for 500 ppm of propylene in a 1% stream at 550°C. The response times of these sensors were found to be strongly dependent on the porosity in the YSZ electrolyte and could be optimized to yield a sensor response time as low as one second. © 2003 The Electrochemical Society. All rights reserved.