Phase diagram calculations that were made previously for the ZrO2-MOm/2(m = 2, 3, 4) systems and for the ZrO2-YO1.5-MOm/2 (M = transition metals) systems have been extended to the ZrO2-YO1.5-CeO2(-CeO1.5) system to make an attempt to explain (1) thermogravimetric (TG) results as a function of oxygen potential, (2) electronic conductivity as a function of oxygen potential, and (3) a miscibility gap observed in air. The interaction parameters for the CeO2-CeO1.5-YO1.5 system were obtained from the reported oxygen nonstoichiometry in CeO2-x and rare earth doped ceria, (Ce,RE)O2-δ. The interaction parameters for the ZrO2-CeO2 subsystem were obtained so as to reproduce the observed miscibility gap at 1273 K. Those thermodynamic properties can reproduce consistently the experimental behaviors of the electronic conductivity and the TG results in the (Zr1-xCex)0.8Y0.2O1.9 solid solutions; these indicate the enhancement of reduction of CeO2.
ASJC Scopus subject areas
- Materials Science(all)
- Physical and Theoretical Chemistry
- Metals and Alloys