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The high oxygen permeability combined with reasonable structural stability of perovskite-type ABO 3−δ compounds is vital for their potential applications in gas separation, solid oxide fuel cells, sensors, etc. Hence, an attempt is made to develop SrCo 0.8 Fe 0.2 O 3−δ -based dense membranes with sol-gel-derived oxalates and study their phase stability and oxygen permeation. While X-ray diffraction confirms the presence of a perovskite-type cubic phase above 800°C, Xray photoelectron spectroscopy reveals the presence of cobalt and iron in 3+ and 4+ oxidation states with O 2 2− , O 2 − and O − species. The electrical conductivity increases up to a characteristic temperature and decreases slowly thereafter via pronounced carrier scattering. A 1.5-mm-thick membrane disp l a y s r e a s o n a b l e o x y g e n p e r m e a b i l i t y o f 1.05 × 10 −6 mol cm −2 s −1 at 900°C but has inadequate stability. Partial substitution of iron with zirconium is shown to improve permeability and stability significantly. Thus, SrCo 0.8 Fe 0.15 Zr 0.05 O 3−δ membrane shows promise for oxygen permeation purposes.

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