A series of perovskite oxides was investigated with regard to their electronic conductivity and O transport properties. The experiments were carried out on pressed samples with ceramic micro-electrodes made from ZrO2-20mol%Y or CeO2-20mol%Gd, versus a large area Pt counter-electrode, at 600 to 750C. Results were presented for Gd1−xSrxCoO3, Gd1−xSrxCo1−yMgyO3, La1−xCaxCrO3 and Gd1−xSrxCrO3. The Gd1−xSrxCoO3, doped with 20 or 40mol%Sr, exhibited good O-ion conductivities of up to 6.0 x 10−4S/cm (Gd0.6Sr0.4CoO3 at 700C in air). This system also exhibited a marked enhancement of the O electrode reaction in contact with ZrO2. The chromites had rather low O-ion conductivities, but exhibited clear catalytic effects for the reduction of O.

Mixed Conduction and Electrode Properties of Doped Cobaltites and Chromites. H.D.Wiemhöfer, H.G.Bremes, U.Nigge: Solid State Ionics, 2004, 175[1-4], 93-8