In order to clarify the chemical properties of the single phases, t′ andκ, in the CeO2-ZrO2system, evolved-oxygen gas analyses (EGA) were performed by heating in a reducing gas and successive oxidations of the resulting pyrochlore phase in O2gas were carried out repeatedly. The rate of oxygen release was analyzed as a function of temperature and time. When the pyrochlore phase was oxidized at 873 K, theκphase appeared. When theκphase was annealed in O2gas at 1323 or 1423 K, a new tetragonal phase, t*, appeared, which released oxygen at the highest temperatures. The oxygen release behavior of theκphase significantly changed, and was dependent on the history of the sample, specifically, whether it had experienced the t*phase. The oxygen release behavior of t′ depended on the temperature where the t′ had gained oxygen after losing a small amount of oxygen. Powder XRD and Raman scattering techniques have been applied to characterize the oxygen release behavior of these t′, t*, andκphases.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry