Kinetic decomposition of La0.3Sr0.7CoO3−δ perovskite membranes during oxygen permeation

In this paper, a study is presented towards the stability of oxygen permeable membranes of perovskite La0.3Sr0.7CoO3−δ in an oxygen pressure gradient. It is shown that phase separation occurs at the oxygen-lean side of the membrane, at 900°C, when the membrane is exposed to streams of air and inert gas at opposite sides of the membrane. It is absent when the (homogenous) oxide is annealed in either flowing air or nitrogen for several days, indicating that the phase separation is induced by the dynamic forces acting during oxygen permeation.