A fast response oxygen sensor based upon a fully-sealed zirconia pump-gauge operated in the potentiometric mode

Abstract

An instrument for fast and continuous measurement of oxygen partial pressure not requiring a reference gas was constructed around a sealed zirconia oxygen pump-gauge sensor operated in the AC mode. By appropriate signal processing of the gauge EMF, the mean oxygen partial pressure within the sensor was determined and maintained constant via a feedback loop. Potentiometric measurement of the oxygen partial pressure in the sample gas was made relative to this controlled internal reference. The response time of the instrument for a step change in oxygen partial pressure from 1 to 10 kPa was only 65 ms.