It was found that O permeation in these materials was very high at moderate temperatures. The materials, BaCo0.95Y0.05O3-δ and CoBa0.90Y0.10O3-δ, consisted of a BaCoO3-δ-like major phase, plus some minor phases. In the case of BaCo0.95Y0.05O3-δ, the minor phases amounted to less than 10% in volume, and the O permeability was equal to 2.7 x 10-7mol/cm2s at 900C, with an activation energy of 31/mol at temperatures of between 900 and 1100C. The BaCo0.95Y0.05O3-δ exhibited the highest O permeation value (3.9 x 10-7mol/cm2s at 900C), and the activation energy for temperatures of between 900 and 1100C was 24kJ/mol. The material, CoBa0.67Y0.33O3-δ, which consisted mainly of 2 unknown cubic phases, exhibited an O permeability of 5 x 10-8mol/cm2s at 900C, with an activation energy of 49kJ/mol at temperatures of between 600 and 900C.

H.W.Brinkman, H.Kruidhof, A.J.Burggraaf: Solid State Ionics, 1994, 68[3-4], 173-6