Structural and dynamical studies of delta-Bi/sub 2/O/sub 3/ oxide ion conductors. I. The structure of (Bi/sub 2/O/sub 3/)/sub 1-x/(Y/sub 2/O/sub 3/)/sub x/ as a function of x and temperature
The authors report the results of both Bragg and diffuse neutron scattering studies of the superionic solid solution, (Bi/sub 2/O/sub 3/)/sub 1-x/(Y/sub 2/O/sub 3/)/sub x/. The Bragg data for polycrystalline samples show that the structural features observed previously in (Bi/sub 2/O/sub 3/)/sub 0.73/(Y/sub 2/O/sub 3/)/sub 0.27/ are present across the entire range of the solid solution, 0.25 < x < 0.42. The number of <111>-displaced anions in the defect fluorite structure decrease with increasing Y/sup 3 +/ content whereas the extent of short-range ordering on the anion sublattice increases. Both of these observations are consistent with the decrease in oxide ion conductivity which occurs as x increases. The basic crystal structure does not change between room temperature and 1023 K, although the unit cell volume increases by 3.78% for x = 0.27, and the number of <111>-displaced anions increases, again consistent with the enhanced conductivity observed at high temperatures. It is suggested that Y/sup 3 +/ stabilizes the fluorite structure by ordering the vacancies on the oxygen sublattice in chains along the <111> and <110> directions.
- Research Organization:
- Leeds Univ., England
- OSTI ID:
- 5587212
- Journal Information:
- J. Solid State Chem.; (United States), Vol. 63:1
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
BISMUTH OXIDES
CRYSTAL STRUCTURE
DYNAMICS
YTTRIUM OXIDES
ANIONS
EXPERIMENTAL DATA
LATTICE PARAMETERS
NEUTRON DIFFRACTION
POWDERS
SPACE DEPENDENCE
SPATIAL DISTRIBUTION
TEMPERATURE DEPENDENCE
VERY HIGH TEMPERATURE
X-RAY DIFFRACTION
BISMUTH COMPOUNDS
CHALCOGENIDES
CHARGED PARTICLES
COHERENT SCATTERING
DATA
DIFFRACTION
DISTRIBUTION
INFORMATION
IONS
MECHANICS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
SCATTERING
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies
360204 - Ceramics
Cermets
& Refractories- Physical Properties