Impedance Characteristics of Platinum Electrodes on Yttria‐Stabilized Zirconia

Abstract
The impedance response of the cell O2,Pt/(Y2O3)0.06 (ZrO2)0.94/Pt,O2 is measured at temperatures between 600 and 850°C and oxygen partial pressures between 10−3 and 1 atm as well as in low vacuum. The experimental data agree very well with those encountered in Reference [1], where surface diffusion of adsorbed oxygen atoms on the platinum electrode, the activity of which obey a Langmuir relationship, is proposed as the rate‐determining step. Current treatment as well as hydrogen treatment of the cell irreversibly increase the interface impedance. The measurements in vacuum confirm that gas phase diffusion is not rate‐limiting.