High temperature stability of Ba0.5Sr0.5Co0.8Fe0.2O3-delta and La0.6Sr0.4Co1-yFeyO3-delta oxygen separation perovskite membranes

作者：Brisotto Mariangela; Cernuschi Federico^*; Drago Francesca; Lenardi Cristina; Rosa Patrizia; Meneghini Carlo; Merlini Marco; Rinaldi Claudia

来源：Journal of the European Ceramic Society, 2016, 36(7): 1679-1690.

DOI：10.1016/j.jeurceramsoc.2016.01.029

• Perovskite membrane
• Oxygen permeation
• Kinetic study
• High temperature stability

The Barium (BSCF) and Lanthanum (LSCF) strontium cobalt-ferrite, are among the most studied mixed ionic electronic conducting materials having interesting properties as Oxygen Transport Membranes. In this paper the two materials are analysed after long term aging at high temperatures and permeation tests. Several characterisation techniques are used to understand degradation mechanisms. Surface layers were analysed by X-ray photoelectron spectroscopy: LSCF is stable, while on BSCF a thin layer of carbonates forms. Quantitative synchrotron radiation diffraction measurements of hexagonal phase content in aged BSCF allows determining Avrami coefficients at 780, 800 and 820 degrees C. This process is associated to the enrichment of Fe in the regions of grains near the lamellar hexagonal phase, as WDS maps show. Built measurements of X-ray Absorption Near Edge Structure (XANES) and the analysis of the Co2p doublet in XPS spectra confirm a reduction of Co ions oxidation number after long time at intermediate temperatures.

• 出版日期2016-6