Journal of Materials Science

, Volume 25, Issue 7, pp 3333–3337 | Cite as

Preparation and properties of KNbO3 via the sol-gel method

  • Azar Nazeri-Eshghi
  • A. X. Kuang
  • J. D. Mackenzie


Sol-gel processing of a solution of niobium and potassium ethoxides in methanol was used to prepare polycrystalline potassium niobate ceramic discs. Gel powders completely crystallized after only 2 h at 600 ° C. Crystallized powders were hot-pressed at pressures less than half of that required in conventional methods. Densities of up to 99% were achieved without encountering the common problem associated with the evaporation of the potassium oxide and subsequent formation of a stable second phase. The variation of dielectric constant with temperature was measured up to several degrees above the Curie temperature (ã420b ° C). Dielectric constants of dense samples were found to be more than one and one-half times greater than that of their single crystal counterparts.


Potassium Dielectric Constant Niobium Curie Temperature Ethoxides 
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Copyright information

© Chapman and Hall Ltd 1990

Authors and Affiliations

  • Azar Nazeri-Eshghi
    • 1
  • A. X. Kuang
    • 1
  • J. D. Mackenzie
    • 1
  1. 1.Department of Materials Science and EngineeringUniversity of CaliforniaLos AngelesUSA

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