A novel combustion route for the preparation of perovskite-type oxygen permeable materials

Ba0.5Sr0.5Co0.8Fe0.2O3−δ perovskite-type oxygen permeable materials were prepared by a novel complexation/combustion (CC) method, where oxygen/air was introduced externally to assist combustion instead of adding an extra oxidant into a precursor solution. This method offers the advantages of facilitating the crystallization of perovskite phase and easy sample treatment. Compared with various self-propagating combustion systems, such as glycerol/nitrates (GlN), glycine nitrates (GN) and EDTA/citrate nitrates (ECN) routes, the CC method yields perovskite products with minimum phase contamination and the highest crystallinity. Additionally, the oxygen permeation tests and SEM studies revealed that the disc-shape membrane made from the CC powder exhibit less structure defects and higher oxygen permeation flux. The complexation/combustion method developed here is an attractive technique for synthesizing perovskite-type oxygen permeable materials.