Combustion synthesis, annealing, and oxygen permeation properties of SrFeCo0.5Oy membranes

Perovskite phase dominant SrFeCo0.5Oy ceramic membranes were made from powders prepared by a glycine–nitrate combustion process (GNP). The sample sintered at 1150 °C consisted of perovskite and spinel phase. The grain size of the sintered sample increased remarkably with the calcination temperature of the starting powder. The phase composition of a coarse-grained sample remained almost unchanged after annealing at 900 °C in air, whereas, annealing of a fine-grained sample resulted in the formation of an intergrowth oxide as a dominant phase. In comparison with solid state reaction (SSR) and sol–gel derived membranes, the GNP-derived membrane exhibited greater oxygen permeability, which could be attributed to the oxygen-deficient perovskite phase that is highly permeable to oxygen.