resumo
The influence of the synthesis conditions on the crystal structure and properties of the oxides of the system GdBaCo2-xFexO5+delta is reported in this article. The materials are prepared by a ceramic method either in air or in an argon atmosphere. Crystal structure characterization is carried out by a combination of powder X-ray diffraction (PXRD) with advanced methods of high resolution transmission electron microscopy (HRTEM), scanning-transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). Thermal expansion coefficients of the oxides decrease with increasing substitution of Co by Fe. Impedance spectroscopy analysis of symmetrical cells using these materials as electrodes reveals area-specific polarization resistance (ASR) values low enough for the use of the oxides as air electrodes in intermediate temperature solid oxide fuel cells (IT-SOFCs).
palavras-chave
FAST OXYGEN DIFFUSION; LAYERED PEROVSKITE; ELECTROCHEMICAL PROPERTIES; ELECTRICAL-PROPERTIES; POWDER DIFFRACTION; PHASE-TRANSITION; CATHODE MATERIAL; GDBACO2-XFEXO6-DELTA; PRBACO2O5+DELTA; GDBACO2O5+X
categoria
Chemistry; Energy & Fuels; Materials Science
autores
Munoz-Gil, D; Perez-Coll, D; Urones-Garrote, E; Amador, U; Garcia-Martin, S
nossos autores
Daniel Muñoz Gil
Bolseiro de pós-Doutoramentoagradecimentos
This work has been supported by MINECO with Projects MAT2013-46452-C4-4-R, MAT2016-78362-C4-4-R, MAT2016-78362-C4-1-R and ENE2015-66183-R and by CM with project MATERYENER3CM-S2013/MIT-2753.