Oxygen permeation results through La1-xSrxCoO3-δ are reported. It is shown that in the temperature region 750 - 775 °C an order-disorder of the oxygen sublattice occurs. The low temperature ordered phase is studied by X-Ray powder diffraction (XRD), neutron diffraction as well as selected area electron diffraction (SAED) together with High Resolution Transmission Electron Microscopy (HRTEM) coupled with Parallel Electron Energy Loss Spectroscopy (PEELS) and Energy Dispersive X-Ray spectroscopy (EDX). Although the long range methods XRD and neutron diffraction showed no indications for an oxygen vacancy ordering, SAED and HRTEM showed micro domains exhibiting an ac x ac x 2ac superstructure, along with regions without indications for a superstructure. The superstructure could be interpreted in terms of an oxygen vacancy ordering due to which a large part of the oxygen vacancies were trapped in regions with the superstructure and so effectively reducing the ionic conductivity. By means of PEELS it was shown that the cobalt ions within the superstructure regions have a higher oxidation state than the cobalt ions in the non-ordered regions.
|Title of host publication||Ceramic membranes I|
|Subtitle of host publication||Proceedings of the First International Symposium on Ceramic Membranes|
|Editors||H.U. Anderson, A.C. Khandkar, M. Liu|
|Place of Publication||Pennington, NJ|
|Publisher||The Electrochemical Society Inc.|
|Number of pages||7|
|Publication status||Published - 28 Jan 1997|
|Event||1st International Symposium on Ceramic Membranes 1995 - Chicago, United States|
Duration: 8 Oct 1995 → 13 Oct 1995
Conference number: 1
|Publisher||The Electrochemical Society, Inc.|
|Conference||1st International Symposium on Ceramic Membranes 1995|
|Period||8/10/95 → 13/10/95|
van Doorn, R. H. E., Bouwmeester, H. J. M., & Burggraaf, A. J. (1997). Phase related oxygen permeation through Sr-doped LaCoO3-δ. In H. U. Anderson, A. C. Khandkar, & M. Liu (Eds.), Ceramic membranes I: Proceedings of the First International Symposium on Ceramic Membranes (pp. 139-145). (Proceedings; Vol. 95-24). Pennington, NJ: The Electrochemical Society Inc..