Abstract
Electrical conductivity measurements on CaTi1−xFexO3−δ (x=0.1, 0.2, 0.3) were performed on polycrystalline pressed and sintered tablets using the van der Pauw four point method in controlled atmospheres. The results were interpreted to reflect n-type, ionic and p-type conductivity at different oxygen partial pressures. An increasing iron content increases the number of oxygen vacancies and increases the ionic conductivity at high temperatures, but also increases the tendency of ordering, which suppresses the ionic conductivity at more moderate temperatures. These findings are in accordance with the phase diagram of the system CaTiO3-CaFeO2.5 based on X-ray and Mössbauer studies.
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Marion, S., Becerro, A.I. & Norby, T. Ionic and electronic conductivity in CaTi1−xFexO3−δ (x=0.1–0.3). Ionics 5, 385–392 (1999). https://doi.org/10.1007/BF02376002
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DOI: https://doi.org/10.1007/BF02376002