Structure and oxygen stoichiometry of SrCo0.8Fe0.2O3−δ and Ba0.5Sr0.5Co0.8Fe0.2O3−δ

McIntosh, Steven and Vente, Jaap F. and Haije, Wim G. and Blank, Dave H.A. and Bouwmeester, Henny J.M. (2006) Structure and oxygen stoichiometry of SrCo0.8Fe0.2O3−δ and Ba0.5Sr0.5Co0.8Fe0.2O3−δ. Solid State Ionics, 177 (19-25). pp. 1737-1742. ISSN 0167-2738

PDF
Restricted to UT campus only: Request a copy
313Kb

Abstract:	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.
Item Type:	Article
Copyright:	© 2006 Elsevier
Faculty:	Science and Technology (TNW)
Research Group:	Inorganic Materials Science (IMS) Inorganic Membranes (IM)
Link to this item:	http://purl.utwente.nl/publications/59211
Official URL:	http://dx.doi.org/10.1016/j.ssi.2006.03.041
Export this item as:	BibTeX EndNote HTML Citation Reference Manager

Repository Staff Only: item control page

Metis ID: 235021