Electrode of stable structure for solid-state electrolytes for electrochemical applications, and use of such an electrode in electrochemical sensors for determining the oxygen content in gases

摘要

A highly loadable electrode of stable structure for solid-state electrolytes for electrochemical applications is proposed which contains a metallic component which catalyses the establishment of a thermodynamic gas equilibrium. Instead of the conventional platinum, the electrode contains at least predominantly rare metals having a melting point of less than 1600 DEG C, and a temperature-resistant, electronically conductive non-metallic solid. The rare metals which can be used are preferably silver and/or palladium, while especially an oxide of the Perovskite type is used as the electronically conductive non-metallic solid. The electrode has proved suitable especially in an electrochemical sensor for the determination of the oxygen content in gases, according to the attached drawing, where it can be used above all as an internal electrode exposed to a comparison gas, even though the measuring electrode can also be designed in this way. It is thus possible to replace the otherwise conventionally used expensive platinum in such electrodes by less expensive rare metals without functional detriment. IMAGE