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

Abstract

The electronic conductivity of scandia-stabilized zirconia doped with 1 mol% CeO2 was measured at 1173 - 1273 K in the oxygen partial pressure range (p(O2)) 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(O2) due to the hole and electron conductions in higher and lower p(O2) regions (> 10-6 and < 10-17 MPa), respectively. Upper deviation of electronic conductivity was observed at 1273 K in p(O2) range of 10-6 - 10-17 MPa. Such a deviation had the p(O2) dependency similar to the product of Ce3+ and Ce4+ concentrations obtained by thermodynamic calculations. 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.