Directional solidification of ZrO2-BaZrO3 composites with mixed protonic-oxide ionic conductivity
authors Carvalho, RG; Fernandes, AJS; Silva, RF; Costa, FM; Figueiredo, FM
nationality International
journal SOLID STATE IONICS
author keywords BaZrO3; ZrO2; Eutectic; Directional solidification; Mixed ionic conductivity
keywords YTTRIA-STABILIZED ZIRCONIA; GRAIN-BOUNDARIES; OXYGEN-ION; CONDUCTORS; SYSTEM; TRANSPORT; CERIA
abstract The synthesis and characterization of directionally solidified Y-doped zirconia-barium zirconate eutectic materials by the laser floating zone technique (LFZ) is presented in the search for novel mixed ionic conductors by protons and oxide ions. Emphasis is placed on the control of the LFZ conditions that promote the solubilization of Y in both eutectic phases, and how the dopant influences the ionic conductivity. Fast growth under constitutional supercooling conditions leads to the development of ZrO2-dendrites above the solidification interface, which are dipped into a finer-interpenetrated network of ZrO2 and BaZrO3. Yttrium-doping of the ZrO2 fluorite-type lattice is favored by the high thermodynamic stability of BaZrO3. However, even low Y-substitution levels in BaZrO3 lead to dominating protonic conduction in the composite under humidified atmospheres below 500 degrees C. At higher temperatures, the proton incorporation is unfavorable, and the total conductivity of the composite is determined by the hole conduction in the Ba(Zr,Y)O-3, and/or oxide-ion conductivity through the (Zr,Y)O-2. (C) 2013 Elsevier B.V. All rights reserved.
publisher ELSEVIER SCIENCE BV
issn 0167-2738
year published 2014
volume 262
beginning page 654
ending page 658
digital object identifier (doi) 10.1016/j.ssi.2013.10.051
web of science category Chemistry, Physical; Physics, Condensed Matter
subject category Chemistry; Physics
unique article identifier WOS:000338810500144
  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