CO2 sensor based on the combination of trivalent Sc3+ ion-conducting Sc-2(WO4)(3) and O2- ion-conducting stabilized zirconia solid electrolytes

A compact carbon dioxide gas sensor was fabricated using a trivalent Sc3+ i on-conducting Sc-2(WO4)(3) solid electrolyte and an oxide anion conducting stabilized zirconia. The time necessary to attain a 90% response for the CO 2 detection was within 1 min. The output response was exactly equal to the Nernstian equation and the 1:1 linear relationship was obtained between the sensor output and the logarithm of the carbon dioxide gas content. A quant itative CO2 gas monitoring was successfully realized with a rapid, continuo us, and reproducible response. (C) 1999 The Electrochemical Society. S1099- 0062(99)05-102-0. All rights reserved.