EMF response of the YSZ based potentiometric sensors in VOC contaminated air

Summary Recent works on potentiometric volatile organic compound (VOC) detection based on oxygen sensor with yttria-stabilized zirconia (YSZ) and modified Pt electrodes is reviewed. Sub-ppm or lower level of VOC contamination in air is now detectable using YSZ based oxygen concentration cell. The VOC contamination fluctuates the concentration of adsorbed oxygen on the Pt sensing electrode, leading to a substantial deviation from the electromotive force (EMF) value predicted by the Nernst equation, E  = ( RT /4 F )ln{ P 1 (O 2 )/ P 2 (O 2 )}. Sensitivity of the Pt electrode is tunable by the coating of the Pt electrode with some ceramic layers tunes, which may vary the concentration of the adsorbed oxygen and even the reaction electron number of oxygen.