A stable Zr-Y co-doped perovskite BaCo0.4Fe0.4Zr0.1Y0.1O3−δ ceramic membrane for highly efficient oxygen separation

Abstract

The development of stable mixed ionic-electronic conducting (MIEC) perovskite ceramic membranes for highly efficient oxygen separation is still a major challenge. Herein, we propose a new dense ceramic membrane of Zr-Y co-doped perovskite BaCo0.4Fe0.4Zr0.1Y0.1O3−δ (BCFZY) for stably separating oxygen from air. The BCFZY membrane demonstrated excellent thermal and chemical stability at elevated temperatures, under Ar and 10–30% CO2-containing atmospheres. A high mechanical strength of 110.9 MPa and improved thermomechanical stability can also be achieved for the BCFZY membrane, much better than classical Ba0.5Sr0.5Co0.8Fe0.2O3−δ with high cobalt content. The oxygen permeability of as-prepared BCFZY membranes was systematically investigated. The 0.5 mm-thick membrane demonstrated a very stable and high oxygen permeate flux of about 1.36 mL·min−1·cm−2 at 900 °C in the run of 100 h with Ar as the sweep gas. Furthermore, the BCFZY membranes exhibited relatively good CO2 resistance showing a flux reduction of only about 25% when 30% CO2 was introduced in the sweep gas. The obtained results demonstrate a good prospect of BCFZY ceramic membrane for highly efficient oxygen separation.