Permeation measurements were performed on 2 layered bismuth based oxide ceramics: a rhombohedral phase belonging to the Bi2O3–CaO system, (Bi2O3)0.73–(CaO)0.27 (BICAO) and a BICOVOX phase. The permeability for these systems was compared to the permeability of a cubic fluorite-type structure with the composition, (Bi2O3)0.75(Er2O3)0.25. A low O permeability was observed for the pure ceramic. As for (Bi2O3)0.75(Er2O3)0.25, the permeability was considerably increased if 40vol%Ag was added to BICAO. In contrast, the permeability was not improved by the addition of Au to BICOVOX. For this latter phase, the O molecular exchange at the surface was clearly the limiting step in O transfer.

Oxygen Permeation in Bismuth-Based Materials - Sintering and Oxygen Permeation Fluxes. E.Capoen, M.C.Steil, G.Nowogrocki, M.Malys, C.Pirovano, A.Löfberg, E.Bordes-Richard, J.C.Boivin, G.Mairesse, R.N.Vannier: Solid State Ionics, 2006, 177[5-6], 483-8