resumo
In this work we report on the combined use of microwave (MW) heating sources for the powder synthesis and the ceramic sintering of Sm and Ca co-doped ceria Ce0.8Sm0.18Ca0.02O1.9 polycrystalline materials for potential application as an electrolyte in intermediate-temperature solid oxide fuel cells (IT-SOFCs). We investigate the crystal structure, ceramic microstructure and the oxygen ion conductivity in detail and compare the latter to conventionally sintered ceramics. MW sintering of ceramic pellets leads to only slightly increased resistivity as compared to conventional sintering, but offers massive energy and time savings for potential industrial production processes. Exceptionally high oxygen ion conductivity without any significant electronic contribution was found in MW synthesized and MW sintered pellets, where the total resistivity, composed of grain boundary and bulk contributions, was found to be in the range of 0.5-1 ka at 500 degrees C. Sm- and Ca co-doped ceria may be well-suited for electrolyte materials in IT-SOFCs. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
palavras-chave
OXIDE FUEL-CELLS; YTTRIA-STABILIZED ZIRCONIA; IONIC-CONDUCTIVITY; ELECTRICAL-PROPERTIES; COMPOSITE ELECTROLYTES; SR2+; HETEROSTRUCTURES; PERFORMANCE; IMPROVEMENT; RELAXATION
categoria
Chemistry; Electrochemistry; Energy & Fuels
autores
Prado-Gonjal, J; Heuguet, R; Munoz-Gil, D; Rivera-Calzada, A; Marinel, S; Moran, E; Schmidt, R
nossos autores
Daniel Muñoz Gil
Bolseiro de pós-Doutoramentoagradecimentos
J.P.-G. acknowledges financial help from the Community of Madrid (Materyener S2009/PPQ-1626) and a PhD scholarship from the Universidad Complutense de Madrid. R.S. wishes to acknowledge the MICINN/MINECO in Spain for granting a Ramon y Cajal Fellowship. Furthermore, this work was supported by the MICINN/MINECO through grant no. MAT 2007-31034 and by the European Union through the FP7-PEOPLE-2007-1-1-ITN SOPRANO network. The authors wish to express their gratitude to Jacobo Santamaria and Carlos Leon for allowing use of and for assistance with the Novocontrol impedance spectroscopy facilities. Thanks to Maria Jose Torralvo for carrying out BET measurements.