Oxygen Permeability of Strontium-Doped LaCoO3-δPerovskites

Abstract

AbstractOxygen permeation rates are reported for 2 mm thick La1-xSrxCoO3-δ(0 ≤x≤0.8) in the temperature range 700 ≤T1100 °C and oxygen partial pressure range 7.0 x 103- 1.0 x 105Pa. With the exception ofx= 0.6 permeation rates increase with an increase in Sr doping level. The oxygen permeation can be described by Wagner theory. An anomaly is observed in the oxygen permeation between 750 - 775 °C, which is attributed to an order-disorder transition. It is further shown that the partial pressure at the low partial pressure side of the membrane has an important influence on the permeation rate. The (calculated) ionic conductivities and oxygen vacancy diffusion coefficients are among the highest reported in literature.