Method of determining concentration of a component in gases and

Abstract

A method of detecting the concentration of a component in gases, by an electrochemical element comprising a pumping cell having a first and a second electrode on a solid electrolyte layer, and a sensing cell comprising a third and a fourth electrode disposed on another solid electrolyte layer, the first and third electrodes being located adjacent to each other, and exposed to the gas to be measured which has been diffused with a predetermined diffusion resistance. A primary pumping current is applied to the pumping cell to control the partial pressure of the component in the atmosphere adjacent to the first and third electrodes. The primary pumping current is controlled so that an electromotive force induced on the sensing cell concides with a predetermined value. The method comprises a step of applying an auxiliary pumping current between the third electrode of the sensing cell, and one of the other three electrodes, for effecting an auxiliary pumping operation so as to cause a change in the partial pressure of the component in the atmosphere adjacent to the third electrode, in the same direction as a change in the partial pressure in the atmosphere adjacent to the first electrode, which is caused by the primary pumping current. Also disclosed is an electrochemical device for practicing the method.