Oxygen Permeability, Electronic and ionic Conductivities and Defect Chemistry of Ceria-Zirconia-Calcia

  • Kawamura, Ken-ichi (Research Institute for Scientific Measurements, Tohoku University) ;
  • Watanabe, Kensuke (Research Institute for Scientific Measurements, Tohoku University) ;
  • Nigara, Yutaka (Research Institute for Scientific Measurements, Tohoku University) ;
  • Kaimai, Atsushi (Research Institute for Scientific Measurements, Tohoku University) ;
  • Kawada, Tatsuya (Research Institute for Scientific Measurements, Tohoku University) ;
  • Mizusaki, Junichiro (Research Institute for Scientific Measurements, Tohoku University)
  • 발행 : 1998.06.01

초록

The total conductivity and oxygen permeation in (Ce1-xZrxO2)0.9(CaO)0.1 solid solutions were measure das a function of temperature and oxygen partial pressure. Empirically, σ at given x and T was expressed essentially by σ=σo2+σeo Po2-1/4, where σo2 and σeo are constant. Applying a standard defect model in which major defects are Cace", Cece' and Vo in ideal solution, we can assign σo2 as the oxide ion conductivity decreases while the electronic conductivity increases with the increase in Zr content. Using the oxide ion and electronic conductivities thus determined, the oxygen permeation flux was calculated for respective Po2 and T conditions at which the measurements were made. The calculated values were found to agree with the observed ones.

키워드

참고문헌

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