Mixed oxygen ionic and electron conducting perovskite oxides [Elektronische Ressource] : issues and possible solutions / Konstantin Efimov

Mixed oxygen ionic and electron conducting perovskite oxides: issues and possible solutions Von der Naturwissenschaftlichen Fakultät der Gottfried Wilhelm Leibniz Universität Hannover zur Erlangung des Grades Doktor der Naturwissenschaften Dr. rer. nat. genehmigte Dissertation von Dipl.-Chem. Konstantin Efimov geboren am 29. März 1980 in Iwanowo (Russland) 2011 Referent: Priv.-Doz. Dr. Armin Feldhoff Korreferent: Prof. Dr. Klaus-Dieter Becker Tag der Promotion: 29.09.2011 Abstract Alkaline-earth and cobalt-based perovskite oxides stand out in the family of mixed oxygen ionic and electron conducting (MIEC) materials as a result of their extraordinary transport properties. These cubic perovskites are renowned for their potential applications toward oxygen separating membranes used in membrane reactors, as well as for cathodes in solid-oxide fuel cells. However, their reliable use can be hindered by phase decomposition of the cubic perovskite structure at intermediate temperatures (773-1073 K), as well as poor chemical stability in the presence of CO . Within the 2scope of the presented thesis, both of these major issues were extensively studied. Seven original research articles were produced during the course of this work, including a discussion of how these problems can be solved. In chapter 2, the decomposition process of (Ba Sr )(Co Fe )O and 0.5 0.5 0.8 0.