EXAFS study of yttria-stabilized zirconia

Journal Article · Sat Mar 01 00:00:00 EST 1986 · J. Am. Ceram. Soc.; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1986.tb07425.x· OSTI ID:5850916

Catlow, C R.A.; Chadwick, A V; Greaves, G N; Moroney, L M

The local structural environments of Y/sup 3 +/ and Zr/sup 4 +/ in 18 wt% Y/sub 2/O/sub 3/-stabilized zirconia were studied using extended X-ray absorption fine structure spectroscopy over the temperature range - 120/sup 0/ to 770/sup 0/C. The measured cation-oxygen distances reflect those of the parent oxides, with the mean Zr-O distance 0.017 nm shorter than the mean Y-O distance. The spread in the Zr-nearest-neighbor and Zr-next-nearest-neighbor distances is considerably larger than observed for Y/sup 3 +/. This result is attributed to the anion vacancies being preferentially sited adjacent to the smaller Zr/sup 4 +/ cation which, with ensuing relaxations, permits a closer contact between Zr/sup 4 +/ and its oxygen neighbors. Thus, the structural environment of these Zr/sup 4 +/ ions resembles that of the 7-coordinated Zr/sup 4 +/ in monoclinic zirconia. Increasing the temperature of the sample results in the local structural environments of the two cations becoming more alike, suggesting that increased anionic mobility leads to an increasingly random distribution of anion vacancies.

• Research Organization: Dept. of Chemistry, Univ. of Keele, Keele, Staffordshire ST5 5AG
• OSTI ID: 5850916
• Journal Information: J. Am. Ceram. Soc.; (United States), Vol. 69:3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ZIRCONIUM OXIDES
VACANCIES
X-RAY SPECTROSCOPY
ANIONS
CATIONS
CERAMICS
HIGH TEMPERATURE
LOW TEMPERATURE
MEDIUM TEMPERATURE
OXYGEN
STABILIZATION
TEMPERATURE EFFECTS
VERY HIGH TEMPERATURE
YTTRIUM OXIDES
CHALCOGENIDES
CHARGED PARTICLES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELEMENTS
IONS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
POINT DEFECTS
SPECTROSCOPY
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
ZIRCONIUM COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies