Preparation and characterization of proton conducting terbium doped strontium cerate membranes

SrCe0.95Tb0.05O3-delta (SCT) membranes with perovskite-type structure were prepared by the citrate method. Both gas-permeable and hermetic membranes c an be obtained through the control of sintering steps. Membranes made from powders treated by an intermediate sintering step tend to be porous and gas -permeable, while hermetic membranes can be formed at lower final sintering temperatures by eliminating the intermediate sintering step. The membranes can be gas-tight even at a relative density of 71%. The density of the mem brane increases with the increase of final sintering temperature. The oxali c acid method does not produce SCT with desired perovskite structure due to deficiency of strontium in the solid precipitates. The SCT membranes show appreciable proton conduction in a hydrogen-containing atmosphere. (C) 1999 Elsevier Science B.V. All rights reserved.