METHOD AND DEVICE FOR DETECTING THE CONCENTRATION OF AN OXYGEN-CONTAINING COMPOUND IN AN ANALYTE GAS

摘要

The invention relates to a method and to a device for detecting the concentration of an oxygen-containing compound in an analyte gas in an external volume that also contains oxygen. The inventive method utilizes a sensor with a first chamber that communicates with the external volume via a first diffusion barrier, and with a second chamber that communicates with the first chamber via a second diffusion barrier. The device is further provided with means for reducing the oxygen concentration in the first chamber and means for detecting the oxygen concentration in the second chamber. The oxygen concentration in the first chamber is reduced during a first phase to a value at which no change in concentration of the oxygen-containing compound can be observed. In a second phase, the oxygen concentration in the first chamber is further reduced to a value at which a reduction of the concentration of the first oxygen-containing compound can also be observed. The difference of the oxygen concentration detected in the second chamber in the first and second phase serves as a measure for the respective concentration.