Effects of synthesis methods on oxygen permeability of BaCe0.15Fe0.85O3-delta ceramic membranes

Dense BaCe0.15Fe0.85O3-6 (BCF1585) ceramic membranes synthesized by the solid-state reaction (SSR) method and EDTA-citric acid (EC) process were investigated by X-ray powder diffraction, total conductivity, oxygen permeation, etc. XRD results revealed the perovskite structure of the powders prepared by the EC process was easier to be developed than that of prepared by SSR method. Membranes derived from EC had higher density, pure phase structure and fewer defects comparing to those derived from SSR method. However, membranes derived from SSR method had higher oxygen permeability. Thickness experiments revealed that the oxygen permeation fluxes of the membranes synthesized by both methods are all jointly controlled by surface exchange and bulk diffusion in the range of 0.7-2.0 mm. The long-term oxygen permeation operation revealed that the membranes derived from both methods exhibit good oxygen permeation stability. (c) 2006 Elsevier B.V. All rights reserved