Double-perovskite Gd1−xPrxBaCo2O5+δ membranes showed appreciable oxygen

permeability at moderate temperatures. The overall oxygen permeation process of

GdBaCo2O5+δ was found to be controlled mainly by the bulk diffusion step with the

membrane thickness larger than 0.8mm, and the limitation by oxygen surface

exchange came into play at reduced thickness of 0.8mm. The electrical conductivity measurement showed Gd1–xPrxBaCo2O5+δ samples possessed a

semiconducting behavior at a wide temperature range below 300C and a metallic

behavior at 300 to 850C with a conductivity of nearly 103S/cm.

Oxygen Permeation and Electrical Transport of Gd1−xPrxBaCo2O5+δ Dense

Membranes. C.Yang, X.Wu, S.Fang, C.Chen, W.Liu: Materials Letters, 2009,

63[12], 1007-9