Electrical conductivity σt of metastable κ-CeZrO4 possessing ordered arrangement of Ce and Zr ions in a manner similar to a pyrochlore-type was measured as a function of temperature and time, and compared with tetragonal metastable t′-(Ce0.5Zr0.5)O2 and t′meta-(Ce0.5Zr0.5)O2 phases possessing random arrangement of the cations. The K disk was prepared by reoxidizing a pyrochlore-type precursor in O2 gas at 873 K. The σt as measured for the κ-CeZrO4 was reproducible as a function of temperatures between 957 and 1190 K. At increasing temperatures above 1233 K, the σt decreased gradually with time due to the phase transition: κ → t′, and became consistent with the t′. Although the κ-CeZrO4 phase is thermodynamically less stable than the t′-(Ce0.5Zr0.5)O2, it was virtually stable up to around 1233 K. It was found from the change in the σt due to the phase transition that the σt for the metastable κ-CeZrO4 was an order of magnitude higher than that for the t′ and was similar to that for the t′meta. It was previously reported that a phase transition, t′meta → t′, occurred above 1143 K. The phase transition, κ → t′, accompanied by redistribution of the cations appeared to occur at higher temperatures than that for t′meta → t′ leaving random cation arrangement. © 2001 Elsevier Science Ltd. All rights reserved.
Izu, N., Kishimoto, H., Omata, T., Yao, T., & Otsuka-Yao-Matsuo, S. (2001). Electrical conductivity of metastable K-CeZrO4 phase possessing ordered arrangement of Ce and Zr ions. Science and Technology of Advanced Materials, 2(3–4), 443–448. https://doi.org/10.1016/S1468-6996(01)00074-2