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Title: Controlling polymorphic structures and investigating electric properties of Ca-doped zirconia using solid state ceramic method

Structural study of Zr{sub 1−x}Ca{sub x}O{sub 2−x} samples with x=0.01–0.15 were prepared using solid state ceramic method. X-ray diffraction analysis revealed a mixture of the high temperature phase and the monoclinic one for the samples with x≤0.05. On the other hand, the formation of a single high temperature cubic phase was observed within a concentration range of x=0.06–0.10. At concentrations higher than 0.10 the calcium zirconate phase was observed besides the dominant high temperature one. Rietveld refinement of the single phase data clearly revealed, that substitution of zirconium by calcium increases both the lattice parameters as well as the tetrahedral bond length. Ionic to electronic conductivity ratio enhanced considerably as Ca-doping level ascends. The dielectric constant shows strong temperature dependence at lower frequencies. The dielectric loss factor increases rapidly with the increase in temperature at lower frequencies, while decreases with the increase in frequency at higher temperatures. The ionic conduction is considered as the dominant process at higher temperatures. - Graphical abstract: Forming a high temperature cubic zirconia phase at 1200 °C using ceramic solid state method and aliovalent cation. - Highlights: • Formation the high temperature cubic polymorph of zirconia using Ca-doping. • Solid state ceramic method was usedmore » for preparing the cubic Ca-doped zirconia. • Substitution of zirconium by calcium increases the lattice parameters and the bond length. • Ionic to electronic conductivity ratio enhanced considerably as Ca-doping level increases.« less
Authors:
 [1] ;  [1] ;  [2] ;  [3] ; ;  [1]
  1. Solid State Physics Department, National Research Center, Dokki, Cairo (Egypt)
  2. Physics Department, Faculty of Science, Helwan University, Helwan (Egypt)
  3. Physical Chemistry Department, National Research Center, Dokki, Cairo (Egypt)
Publication Date:
OSTI Identifier:
22486731
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 228; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BOND LENGTHS; CALCIUM COMPOUNDS; CATIONS; CERAMICS; CONCENTRATION RATIO; DIELECTRIC MATERIALS; DOPED MATERIALS; FREQUENCY DEPENDENCE; IONIC CONDUCTIVITY; LATTICE PARAMETERS; MONOCLINIC LATTICES; PERMITTIVITY; SOLIDS; TEMPERATURE DEPENDENCE; X-RAY DIFFRACTION; ZIRCONATES; ZIRCONIUM OXIDES