Junho 2014 vol. 2 num. 3 - 1st International Seminar on Industrial Innovation in Electrochemistry
Artigo Completo - Open Access.
New Ionic Conductor as Solid Electrolyte for Solid Oxide Fuel Cell Application
In this work, ceria-doped electrolytes with general formula of Ce0.8Y0.2-xLaxO1.9 (x=0.00; 0.05; 0.10; 0.15; 0.20) were synthesized by combustion method, using glycine as a fuel. The phase identification and morphology of the powders was studied by X-ray diffraction (XRD), surface area measurements (BET) and Raman spectroscopy. The consistency of particle sizes, calculated by the Scherrer formula, and BET measurements suggests that all as-synthesized powders were composed of weakly agglomerated crystallites. After the sintering process (1450 °C/5h) all pellets reach relative densities above 94% of the theoretical density. The contributions of grains and grain boundaries to the total conductivity, were investigated by a.c. impedance spectroscopy, in temperature range of 200-500 °C. The results show that the substitution of the yttrium by lanthanum mainly affects the grain boundary conductivity.
Palavras-chave: doped-ceria, SOFC, solid electrolyte, fuel cells,
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Ferreira, R.; Berton, M.A.C.; "New Ionic Conductor as Solid Electrolyte for Solid Oxide Fuel Cell Application", p. 117-129 . In: In Proceedings of the 1st International Seminar on Industrial Innovation in Electrochemistry [=Blucher Chemistry Proceedings]. São Paulo: Blucher, 2014.
São Paulo: Blucher,
ISSN 2318-4043, ISBN: 978-85-8039-088-9
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