Oxygen permeation properties of Bi-doped La0.8Sr0.2FeO3−δ planar ceramic membranes at intermediate temperature

•The oxygen permeation performance was tested by a novel electrochemical method based on limiting current instead of gas chromatography at the first time.•A “porous-transition-dense” three-layer of porous 3YSZ/dense 3YSZ-La0.8−xBixSr0.2FeO3-δ/dense La0.8−xBixSr0.2FeO3-δ membrane was successfully fabricated by tape casting, hot-pressing and co-sintering technology.•The best oxygen permeability of La0.4Bi0.4Sr0.2FeO3-δ membrane could reach 1.13 mL min−1 cm−2 at 800 °C with 20% oxygen partial pressure.•The La0.4Bi0.4Sr0.2FeO3-δ membrane demonstrated excellent long-term stability and thermal cycle stability at 800 °C under 1.6 V for 150 h and subsequent 11 times thermal cycling between 700 °C and 800 °C.