Enhancing the oxygen permeation rate of Ba0.5Sr0.5Co0.8Fe0.2O3 − δ membranes by surface loading Co3O4 nanorod catalysts

•Co3O4 nanorod catalysts were self-assembled on the surface of Ba0.5Sr0.5Co0.8Fe0.2O3 − δ membranes.•Co3O4 nanorod catalyst improves the surface exchange reaction of BSCF membrane.•With the modification of Co3O4 catalysts, the oxygen permeation rate of BSCF membrane was significantly improved.

To modify the oxygen permeability of Ba0.5Sr0.5Co0.8Fe0.2O3 − δ (BSCF) membrane, Co3O4 nanorod catalysts were self-assembled onto the surface of the BSCF membrane by a hydrothermal process. Phase structures and morphology of the BSCF membrane self-assembled with Co3O4 nanorod catalysts were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results show that Co3O4 nanorods with spinel structure and of about 100 nm in diameter and 3 μm in length were grown on the surfaces of BSCF membrane. The loading of Co3O4 nanorods can effectively improve the oxygen permeability of BSCF membrane. At 600 °C, the oxygen permeation rate of BSCF membrane with 1 mm in thickness modified by Co3O4 nanorod catalysts reaches 0.47 ml · min− 1 · cm− 2, which is 11.5 times higher than that of the bare BSCF membrane under Air/He gradient. At 850 °C, the oxygen permeation rate of the modified BSCF membrane reaches 1.76 ml · min− 1 · cm− 2, which is 0.3 ml · min− 1 · cm− 2 higher than that of bare BSCF membrane.