Defect Structure and n-Type Electrical Properties of SrCe[sub 0.95]Eu[sub 0.05]O[sub 3−δ]

The effect of defect structure on the electrical conductivity for Eu-doped was studied in a reducing range of A defect model was derived and verified by computational simulation against both electrical conductivity data and Brouwer-type defect equilibria. At higher temperatures, part of the conductivity was due to oxygen vacancies and electrons. At low temperature, protonic conduction dominated. The measured total conductivity is proportional to in the temperature range of 650-750°C, and to at 800°C in wet atmospheres, because of a transition from ionic- to electronic-dominant conduction. The results agree with a derived defect model based on the equilibrium equation for the valence change of Eu ions between trivalent and divalent.