Abstract
In this work, ceria-doped electrolytes with general formula of Ce0.8Y0.2xLaxO1.9 (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. Key-words: doped-ceria, SOFC, solid electrolyte, fuel cells 13 ARICLE TH 118 New Ionic Conductor as Solid Electrolyte for Solid Oxide Fuel Cell Application
Highlights
INTRODUCTIONThe present work was presented in the INTERCORR 2013 in Portuguese language and is presented here by permission of Cigré-Brasil [1] and is a contribution to the First International Seminar on Innovation in Electrochemical Industry held in September, 2013 in Curitiba-PR, Brasil
The present work was presented in the INTERCORR 2013 in Portuguese language and is presented here by permission of Cigré-Brasil [1] and is a contribution to the First International Seminar on Innovation in Electrochemical Industry held in September, 2013 in Curitiba-PR, Brasil.Solid oxide fuel cells (SOFCs) can provide high-energy conversion efficiency for a variety of applications ranging from large scale power plants to mobile applications for vehicles and portable electronics [2, 3]
Materials based on doped ceria are considered the most promising electrolytes with sufficient electrical properties to operate in that temperature range [4, 5]
Summary
The present work was presented in the INTERCORR 2013 in Portuguese language and is presented here by permission of Cigré-Brasil [1] and is a contribution to the First International Seminar on Innovation in Electrochemical Industry held in September, 2013 in Curitiba-PR, Brasil. Yttria stabilized zirconia (YSZ), commonly used as an electrolyte material in SOFCs, requires temperatures above 800 °C for the cell operation, leading to high costs of interconnectors and other construction materials, as well as problems with thermal degradation and thermal expansion mismatch. To overcome these problems, great efforts have been made to lower the operating temperature of SOFCs to the temperature range of 500-700 °C. Various studies have been published on co-doped ceria, most of them report the influence of the substitution of the dopants on the total ionic conductivity only. We evaluate the influence of the substitution of Y by La on the grain and grain boundary conductivities
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
