High-pressure synthesis and properties of CeO2-ZrO2 solid solution

Autor: Zhe Lu, Quanyong Wang, Zhiguo Liu, Wenhui Su, Da-Peng Xu, Gongmu Zhang
Rok vydání: 2001
Předmět:
Zdroj: Chinese Science Bulletin. 46:801-805
ISSN: 1861-9541
1001-6538
DOI: 10.1007/bf02900427
Popis: Using nanoparticles of CeO2 and ZrO2 prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2 solid solution (c-Ce0.5Zr0.5O2) has been synthesized under 3.1 GPa at 1073 K for the first time. The structure of the c-Ce0.5Zr0.5O2 has not been changed before and after annealing at 773 K for 1 h. Only an unknown EPR signal (g = 1.990) has been observed in the c-Ce0.5Zr0.5O2 and not varied after annealing at 773 K for 1 h, which exhibited that there exists no Ce3+ in the c-Ce0.5Zr0.5O2 and the Ce4+ has not been reduced into Ce3+ after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (sigma =1.2 x 10(-5) S/cm at 823 K, sigma = 2.1 x 10(-3) S/cm at 1123 K) is the same as that of CeO2, but smaller than that of Y2O3-stabilized ZrO2. A marked curvature at T = 823 K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 823 K is lower than that above 823 K, and the reason has been discussed.
Databáze: OpenAIRE
Externí odkaz: