Assessment of the electronic conductivity of core-shell, Fe-doped LSGM ceramics by impedance spectroscopy

被引:2
作者
Gomes, Eduarda [2 ]
Mather, Glenn C. [3 ]
Figueiredo, Filipe M. [1 ]
Marques, Fernando M. B. [1 ]
机构
[1] Univ Aveiro, CICECO, Ceram & Glass Engn Dept, P-3810193 Aveiro, Portugal
[2] Polytech Inst Viana do Castelo, Sch Management & Technol, P-4900348 Viana Do Castelo, Portugal
[3] CSIC, Inst Ceram & Vidrio, E-28049 Madrid, Spain
关键词
Lanthanum gallate; Mixed conductor; Grain boundary engineering; Impedance spectroscopy; Electronic conductivity; OXYGEN PERMEATION PROPERTIES; OXIDE FUEL-CELLS; ELECTRICAL-PROPERTIES; LANTHANUM GALLATE; TRANSPORT-PROPERTIES; IONIC-CONDUCTIVITY; MIXED CONDUCTORS; SOLID-SOLUTIONS; MEMBRANES; LAGAO3;
D O I
10.1016/j.ssi.2011.03.006
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The structure, microstructure and low-temperature electrical properties of core-shell-type mixed conductors based on lanthanum gallate with Fe-doped grain boundaries are analyzed in depth. Electron probe microanalysis revealed that the iron concentration in the grain-boundary regions (shell) is below 1 at.% and their thickness is no more than 1.5 mu m. The low-temperature (<400 degrees C) electronic conductivity is enhanced by up to 2-3 orders of magnitude with respect to the corresponding undoped ceramics, as revealed by the analysis of impedance spectra combined with microstructural information. The electronic transport numbers lie in the range between 0.35 and 0.1 at 275 to 400 degrees C, decreasing at higher temperatures, where the influence of grain boundaries on the overall transport properties vanishes and the ionic conductivity increases. (C) 2011 Published by Elsevier B.V.
引用
收藏
页码:11 / 17
页数:7
相关论文
共 35 条
[1]   Ionic and electronic conduction in Fe and Cr doped (La,Sr)GaO3-delta [J].
Baker, RT ;
Gharbage, B ;
Marques, FMB .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1997, 144 (09) :3130-3135
[2]   MIXED CONDUCTION AND DEFECT STRUCTURE OF ZRO2-CEO2-Y2O3 SOLID-SOLUTIONS [J].
CALES, B ;
BAUMARD, JF .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1984, 131 (10) :2407-2413
[3]   MICROSTRUCTURAL DEVELOPMENT, ELECTRICAL-PROPERTIES AND OXYGEN PERMEATION OF ZIRCONIA-PALLADIUM COMPOSITES [J].
CHEN, CS ;
BOUKAMP, BA ;
BOUWMEESTER, HJM ;
CAO, GZ ;
KRUIDHOF, H ;
WINNUBST, AJA .
SOLID STATE IONICS, 1995, 76 (1-2) :23-28
[4]   Transport Properties of Fluorite-Type Ce0.8Pr0.2O2-δ: Optimization via the Use of Cobalt Oxide Sintering Aid [J].
Fagg, Duncan P. ;
Garcia-Martin, Susana ;
Kharton, Vladislav V. ;
Frade, Jorge R. .
CHEMISTRY OF MATERIALS, 2009, 21 (02) :381-391
[5]  
FENG M, 1994, EUR J SOL STATE INOR, V31, P663
[6]   Grain boundary Fe-doping effects in LSGM [J].
Gomes, E. ;
Figueiredo, F. M. ;
Marques, F. M. B. .
SOLID STATE IONICS, 2008, 179 (21-26) :900-903
[7]   Microstructural effects on the electrical properties of grain boundary Fe-doped LSGM [J].
Gomes, E. ;
Marques, F. M. B. ;
Figueiredo, F. M. .
SOLID STATE IONICS, 2008, 179 (27-32) :1325-1328
[8]   Mixed conduction induced by grain boundary engineering [J].
Gomes, E. ;
Figueiredo, F. M. ;
Marques, F. M. B. .
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, 2006, 26 (14) :2991-2997
[9]   Processing and electrical conductivity of lanthanum gallate core-shell heterostructures [J].
Gomes, E. ;
Figueiredo, F. M. ;
Marques, F. M. B. .
BOLETIN DE LA SOCIEDAD ESPANOLA DE CERAMICA Y VIDRIO, 2006, 45 (03) :144-149
[10]   Conductivity of La0.95Sr0.05Ga0.90Mg0.10O3-δ obtained by mechanical activation [J].
Gomes, E ;
Soares, MR ;
Figueiredo, FM ;
Marques, FMB .
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, 2005, 25 (12) :2599-2602