STUDY OF SOLID ELECTROLYTE POLARIZATION BY A COMPLEX ADMITTANCE METHOD

The polarization behavior of zirconia-yttria solid electrolyte specimens with platinum electrodes has been studied over a temperature range of 400° to 800°C and a wide range of oxygen partial pressures. The complex admittance of these specimens was determined over a frequency range from d.c. to 100kHz. An analysis of these data in the complex admittance plane indicated the presence of three polarizations: (1) an electrode polarization characterized by a double layer capacity and an effective resistance for the overall electrode reaction, 1 2O2(gas) + 2e(platinum) {leftwards paired arrows} O2- (electrolyte); (2) a capacitive-resistive electrolyte polarization, probably corresponding to a partial blocking of oxygen ions at the electrolyte grain boundaries by an impurity phase there; and (3) a pure ohmic electrolyte polarization. © 1969.