Mixed oxide ion and electronic conductivity in perovskite-type SrSnO3 by Fe substitution

The electrical conductivity properties of Fe-substituted SrSnO3 perovskite-type oxides as a function of temperature and oxygen partial pressure are presented. SrSn1−xFexO3−δ (0≤x≤1) was prepared by conventional solid state reaction in air using SrCO3, SnO2 and FeC2O4 · 2H2O. The total electrical conductivity increases with increasing Fe content. Compounds containing low Fe contents (x<0.5) are mixed oxide ion and electronic conductors in the oxygen partial pressure range between 10−23 and 0.21 atm with predominant n-type and p-type electronic conduction at low and high oxygen partial pressure, respectively. SrSn1−xFexO3−δ with high Fe-content (x>0.5) is found to be a predominant electronic conductor over the entire oxygen partial pressure regime (10−23–0.21 atm). The average oxide ion transference number is found to be in the range 0.1–0.5 at 600–850 °C for x=0.1–0.2.