Electrotransport Characteristics of Ceramic and Single Crystal Materials with the (ZrO2)0.89(Sc2O3)0.10(Y2O3)0.01 Composition

Resumo

The comparative analysis of electrotransport characteristics and structure of ceramic and single crystal solid electrolytes with the (ZrO₂)_0.89(Sc₂O₃)_0.10(Y₂O₃)_0.01 composition is carried out before and after their life tests. It is shown that before the life tests, the specific conductivities of single-crystal and ceramic materials virtually coincide. During the 3000 h life tests, the specific ionic conductivity decreases for both single crystal and ceramic samples down to about 0.1 S cm^–1 but the degradation of conductivity in single crystal proceeds more slowly as compared with the ceramic material. The reason for degradation of electrotransport characteristics in the single crystal is associated with the transition of its bulk structure from the t′′ phase to a phase with the higher degree of tetragonality, whereas in the ceramic material, in addition to the latter process, a rhombohedral phase appears presumably along grain boundaries.