Author: Mcintosh, S.; Vente, J.; Haije, W.; Blank, D.; Bouwmeester, H.
Description: High temperature X-ray diffraction (HT-XRD), temperature programmed desorption (TPD), thermogravimetric analysis–differential thermal analysis (TGA/DTA) and neutron diffraction were combined to determine the structure and oxygen stoichiometry of SrCo0.8Fe0.2O3−δ (SCF) and Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) up to 1273 K in the pO2 range of 1 to 10− 5 atm. Formation of the vacancy-ordered brownmillerite phase, SrCo0.8Fe0.2O2.5, was observed as a region of zero oxygen release in the TPD measurements and confirmed by HT-XRD and TGA/DTA. No ordering was observed in the BSCF system by any of the techniques utilized in this work. The oxygen vacancy concentration of BSCF was found to be considerably higher than that of SCF and always higher than that of the ordered brownmillerite phase of SCF, δ = 0.5. The combination of a high vacancy concentration and absence of ordering leads to higher oxygen permeation fluxes through BSCF membranes in comparison to SCF.
Subject Headings: Perovskite-type oxides; Membranes; Oxygen non-stoichiometry; Order-disorder transitions; Neutron scattering
Keywords: Structure and oxygen stoichiometry of SrCo0.8Fe0.2O3-[delta] and Ba0.5Sr0.5Co0.8Fe0.2O3-[delta]
Publication year: 2006
Journal or book title: Solid State Ionics
Volume: 177
Issue: 19-25
Pages: 1737-1742
Find the full text : https://www.utwente.nl/en/daveblank/publications/pdf-files/SSI177(2006)1737.pdf
Find more like this one (cited by): https://scholar.google.com/scholar?cites=948168254831039877&as_sdt=1000005&sciodt=0,16&hl=en
Type: Journal Article
Serial number: 2799