ELECTRODE MATERIAL FOR HIGH TEMPERATURE OXYGEN PARTIAL PRESSURE ELECTROCHEMICAL SENSORS - STRONTIUM DOPED LANTHANUMCHROMITE
The electrochemical behavior of 20 % strontium doped lanthanum chrome (SDLC), deposited onto an 8 % yttria stabilized zirconia (YSZ) solid electrolyte, has been investigated. Th electromotive force developed across the interface SDLC/YSZ and a Pt/YSZ reference at 0.21 atm (air) corresponds to the Nernst theoretical relationship. This behavior has been tested between 700 degrees and 1000 degrees C in the ranges 10 degrees -10**-5 and 10**13 - 10**-20 atmospheres of oxygen, the lower pressures by the equilibrium of carefully calibrated steam and hydrogen mixtures. Although not demonstrated, it is probable that the oxygen pressure range of applicability of this mixed oxide electrode covers the entire field of pure ionic conductivity of any zirconia-based electrolyte. The fair agreement between the measured values and the theoretical ef values, the resistance of the electrode layer to scaling, as well as its good thermodynamic stability, suggests SDLC as a possible alternative to platinum in high temperature oxygen pressure sensors.
Bibliographic Reference: REV.SCI.INSTRUM., VOL. 54 (1983), NO.4, PP. 486-492
Record Number: 1989122031600 / Last updated on: 1987-01-01
Available languages: en