The O exchange and transport properties of the perovskite-type oxides Ba0.5Sr0.5Co0.8Fe0.2O3−x (BSCF5582) and Ca0.5Sr0.5Mn0.8Fe0.2O3−x (CSMF5582) were investigated by O permeation as well as electrical conductivity relaxation experiments. The temperature dependence of the O permeation flux JO2 of BSCF5582 at 600 to 950C shows a transition from a low-temperature region with higher activation energy to a high temperature region with lower activation energy. Complementary, the chemical surface exchange coefficient kchem, the chemical diffusion coefficient Dchem and their activation energies were determined from conductivity relaxation experiments at 600 to 750C and 70Pa < PO2 < 3kPa.

Oxygen Transport Properties of Ba0.5Sr0.5Co0.8Fe0.2O3−x and Ca0.5Sr0.5Mn0.8Fe0.2O3−x Obtained from Permeation and Conductivity Relaxation Experiments. E.Girdauskaite, H.Ullmann, V.V.Vashook, U.Guth, G.B.Caraman, E.Bucher, W.Sitte: Solid State Ionics, 2008, 179[11-12], 385-92