Simultaneous Enhancement of H2 and O2 Permeation in Proton Ceramic Honeycomb-Structured Hollow Fiber Membranes via Fe3+ and Y3+ Co-Doping

The high-temperature proton ceramic membranes with simultaneous separation of hydrogen and oxygen exhibit promising applications in the catalytic conversion field. However, their separation performance often relies on external electrical circuits, which limits practical application. To overcome this limitation, doping strategies have emerged as a viable approach to develop triple-conducting (H+/e−/O2−) membranes for simultaneous hydrogen and oxygen separation in non-electrochemical mode. In this study, honeycomb-structured hollow fiber membranes were fabricated, and the effects of varying Fe3+ and Y3+ doping concentrations on hydrogen and oxygen permeation fluxes were systematically investigated. At the Fe3+ doping level of 0.2 mol, the oxygen permeation flux of 0.692 mL min−1 cm−2 in BaCe0.6Zr0.2Fe0.2O3−δ (BCZF) was achieved at 1000 °C, while the hydrogen permeation flux was 0.201 mL min−1 cm−2. The BaCe0.55 Fe0.05Zr0.2Y0.2O3−δ (Fe-BCZY) hollow fiber membrane can enhance the hydrogen permeation flux by 75% at 1000 °C. Furthermore, during the simultaneous permeation of hydrogen and oxygen, a 1.7-fold enhancement in hydrogen permeation performance was achieved for the Fe-BZCY hollow fiber membrane at 1000 °C, and with oxygen permeation flux of 1.76 mL min−1 cm−2 at the same temperature. More significantly, a hydrogen permeation flux of 0.34 mL min−1 cm−2 can be achieved at 700 °C under simultaneous hydrogen and oxygen permeation, which is favorable for the application of membrane reactors in catalytic reactions.