Local charge disproportion in a high-performance perovskite
- verfasst von
- Mirko Arnold, Qiang Xu, Frans D. Tichelaar, Armin Feldhoff
- Abstract
The temperature-dependent local charge disproportion in the (Ba 0.5Sr0.5)(Co0.8Fe0.2)O 3-δ perovskite-type oxide (denoted as BSCF) was monitored by in situ electron energy-loss spectroscopy applying monochromized electrons in a transmission electron microscope. At elevated temperatures, oxygen is removed from the crystal lattice in these perovskite-type oxides that is due to a reduction of the transition metal sites. To determine the site-specific valence in the BSCF perovskite, we measured the cobalt and iron L-edges and the oxygen K-edge on increasing the temperature from 298 to 1223 K. It was found that the loss of oxygen at elevated temperatures is mainly due to a reduction of the cobalt site compared to the iron site. The understanding of the site specific redox behavior in this material is important in explaining its long-term instability at intermediate temperatures, which has not been elucidated priory this study.
- Organisationseinheit(en)
-
Institut für Physikalische Chemie und Elektrochemie
- Externe Organisation(en)
-
Delft University of Technology
- Typ
- Artikel
- Journal
- Chemistry of Materials
- Band
- 21
- Seiten
- 635-640
- Anzahl der Seiten
- 6
- ISSN
- 0897-4756
- Publikationsdatum
- 24.02.2009
- Publikationsstatus
- Veröffentlicht
- Peer-reviewed
- Ja
- ASJC Scopus Sachgebiete
- Allgemeine Chemie, Allgemeine chemische Verfahrenstechnik, Werkstoffchemie
- Elektronische Version(en)
-
https://doi.org/10.1021/cm802779f (Zugang:
Geschlossen)
