Electronic Conductivity of Scandia-Stabilized Zirconia Doped with 1 mol% CeO2

The electronic conductivity of scandia-stabilized zirconia doped with 1 mol% CeO2 (1 mol% CeO2 - 10 mol% Sc2O3 - 89 mol% ZrO2, 1Ce10ScSZ) was measured at 1173 -1273 K in the oxygen partial pressure range (p(O-2)) of 10(-4) - 10(-20) MPa. At 1273 K, the electronic conductivity of 1Ce10ScSZ was in proportion to the 1/ 4 and -1/ 4 power of p(O-2) due to the hole and electron conductions in higher and lower p(O-2) regions (> 10(-6) and < 10(-17) MPa), respectively. Upper deviation of electronic conductivity was observed at 1273 K in p(O-2) range of 10-6 -10-17 MPa. Such a deviation had the p(O-2) dependency similar to the product of Ce3+ and Ce4+ concentrations obtained by thermodynamic calculations. Interestingly, the deviation of electronic conductivity disappeared at 1173 K. This indicates that the activation energy of electronic conduction contributed by 1 mol% Ce dopant was significantly higher than 2.01 eV reported for (CexZr1-xO2) 0.8(YO1.5)(0.2) with Ce content of x = 0.1.