Oxygen permeability of perovskite-type Y1−xMxBa2Cu3O7−δ (M = La, Ca) membranes

Oxygen permeability of dense perovskite-type Y1−xLaxBa2Cu3O7−δ (x = 0.1, 0.3, 0.5, 0.8 and 1.0) and Y1−yCayBa2Cu3O7−δ (y = 0.1, 0.2, 0.3 and 0.4) membranes were investigated under an air/He gradient in a temperature range from 750 to 950 °C. The results indicate that doping of La or Ca has great effects on the oxygen permeability. Oxygen permeation flux of Y1−xMxBa2Cu3O7−δ (M = La, Ca) membrane increases with M substitution for Y in YBa2Cu3O7−δ, and has an obvious increase at about 900 °C due to an order–disorder transition of the oxygen vacancies in the membrane material. Maximum oxygen fluxes of 0.92 and 0.77 μmol/s cm2 are obtained for LaBa2Cu3O7−δ (x = 1.0) and Y0.8Ca0.2Ba2Cu3O7−δ (y = 0.2) membranes with thickness 1.0 mm at 950 °C, respectively.