Lanthanum oxide as a scavenging agent for zirconia electrolytes
authors Carvalho, T; Antunes, E; Calado, J; Figueiredo, FM; Frade, JR
nationality International
journal SOLID STATE IONICS
author keywords Zirconia; Solid electrolyte; Impurity; Scavenging; Grain boundary conductivity
keywords YTTRIA-STABILIZED ZIRCONIA; GRAIN-BOUNDARY CONDUCTION; DOPED CERIA; MICROSTRUCTURE; IMPROVEMENT; PHASE
abstract The present work demonstrates that additions of lanthanum oxide can counter the negative grain boundary effects of relatively high silica contents in 8 mol% yttria-stabilized zirconia (YSZ). This can be predicted by thermodynamic analysis, showing strong affinity between silica and lanthanum oxide at typical sintering temperatures. Microstructural analysis revealed the onset of La- and Si-rich precipitates, and impedance spectroscopy confirmed a positive impact on grain boundary conductivity. Gradual oversaturation of lanthana in YSZ with decreasing temperature allows one to extend these effects by heat treatment at intermediate temperatures. This procedure enhances the positive effects of additions of lanthana on the specific grain boundary conductivity, while minimizing the negative impact on bulk conductivity. (C) 2012 Elsevier B.V. All rights reserved.
publisher ELSEVIER SCIENCE BV
issn 0167-2738
year published 2012
volume 225
beginning page 484
ending page 487
digital object identifier (doi) 10.1016/j.ssi.2012.02.037
web of science category Chemistry, Physical; Physics, Condensed Matter
subject category Chemistry; Physics
unique article identifier WOS:000311873400099
  ciceco authors
  impact metrics
journal analysis (jcr 2017):
journal impact factor 2.751
5 year journal impact factor 2.607
category normalized journal impact factor percentile 58.483
dimensions (citation analysis):
altmetrics (social interaction):



 


Sponsors

1suponsers_list_ciceco.jpg