It was recalled that the use of perovskite mixed ionic–electronic conducting membranes required high O permeation fluxes. In this regard, an improvement in the permeation rates through a La0.6Sr0.4Fe0.9Ga0.1O3-δ membrane was obtained by modifying the surface by controlling the average grain size of the perovskite material or by coating the surface with a thin layer of La0.6Sr0.4Co0.8Fe0.2O3-δ. In both cases, the permeation-limiting regime was determined and the O surface coefficient and diffusion coefficient were evaluated. A low value of the former was found to be the most critical parameter for improving membrane performance.

Oxygen Permeation in La0.6Sr0.4Fe0.9Ga0.1O3–δ Dense Membrane - Effects of Surface Microstructure. G.Etchegoyen, T.Chartier, P.Del-Gallo: Journal of Solid State Electrochemistry, 2006, 10[8], 597-603