Investigation on different valence B-site ions doped Pr0.6Sr0.4FeO3-δ ceramic membrane for hydrogen production from water splitting

Abstract

This study investigates the different valence B-site ions doped on perovskite-type oxygen transport membrane for hydrogen production by water splitting. Perovskite-type Pr0.6Sr0.4Fe0.9M0.1O3-δ (PSFM, M = Fe, Al, Zr, and W) are fabricated successfully by the sol-gel method and form dense membranes with orthorhombic structure. The microstructure, chemical stability, and hydrogen production performance of membranes are studied systematically. The doping of Al3+, Zr4+, and W6+ ions can enhance membranes chemical stability and long-term stability significantly, which is due to the increase of average binding energy and decrease of the valence of B-site ions. Because of higher oxygen vacancy content and lower oxygen vacancy formation energy, the PSFA membrane shows the highest hydrogen production rate of 1.07 mL min−1·cm−2 at 900 °C and stabilizes at about 1.0 mL min−1·cm−2 on long-term test. The performance degradation of PSFM membranes is attributed to the much valence variation of B-site Fe3+/4+ ions and the oxygen vacancy-related phase transition.