The specific conductivity and thermal electromotive force coefficient of Sr- and Ni-doped La0.9Sr0.1Co0.9Ni0.1O3−δ were measured at 1023 to 1223K and 10−6 to 1atm. The oxide was found to exhibit metallic-type conductivity (800 to 1150S/cm) and small positive thermal electromotive force coefficients. A joint analysis of the thermodynamic characteristics of point-defect formation and the temperature- and PO2-dependences of conductivity and thermal electromotive force showed that charge was transferred, within the oxide, by small-radius polarons via the hopping mechanism. The role of polarons was played by electrons, MeCo’, and holes, MeCo•, localized on 3d transition metals.

The Thermodynamic Characteristics of Point Defects and the Mechanism of Charge Transfer in Lanthanum Cobaltite Doped with Strontium and Nickel. A.N.Petrov, V.A.Cherepanov, T.V.Aksenova, L.Y.Gavrilova: Russian Journal of Physical Chemistry A, 2006, 80[1], S134-9