Complex modulation of the crystal structure of a layered perovskite. A promising solid-oxide-fuel-cell cathode. Issue 26 (15th June 2016)

• Record Type: Journal Article
• Authors: Martínez de Irujo-Labalde, Xabier; Muñoz-Gil, Daniel; Urones-Garrote, Esteban; Ávila-Brande, David; García-Martín, Susana
• Is Part Of: Journal of materials chemistry. Volume 4:Issue 26(2016)
• Page Start: 10241
• Page End: 10247
• Publication Date: 2016-06-15
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6ta03307e
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Excellent performance as a cathode material for IT-SOFCs is found in (GdBa)0.8 Ca0.4 Co0.6 Fe1.4 O6− δ related to a complex crystal superstructure based on ordering of Gd, Ba and Ca in combination with different coordination polyhedral of Co and Fe and layered-location of anion vacancies. Abstract : Layered-type perovskites have been the focus of research in the last few years due to their outstanding properties as solid oxide fuel cell oxygen electrodes. The synthesis of a new (GdBa)0.8 Ca0.4 Co0.6 Fe1.4 O6− δ layered perovskite as a single phase as well as the crystal structure determination and catalytic activity for oxygen reduction is reported. Highly advanced methods of transmission electron microscopy have been used for structure determination at atomic resolution. The oxide shows a complex modulation of the crystal structure associated with layered-type ordering of the Gd, Ba and Ca atoms in combination with formation of different coordination polyhedra of the Fe and Co atoms. Location of the anion vacancies within particular highly ion-conducting layers of the crystal structure has been achieved by phase image reconstruction. This material exhibits excellent electrochemical behaviour and thermal stability for use as an air electrode in IT-SOFCs.