Electron-Ion Transport in ZrO2-Y2O 3-CeO2 Ceramics

C. M. Chun, J. D. Mumford, J. Patel, T. A. Ramanarayanan

Research output: Contribution to journalArticle

3 Scopus citations

Abstract

Simultaneous conduction of oxide ions and electrons in solid ceramic systems provides the capability for oxygen transport under a concentration gradient without the need for an externally applied electric field. In the present study, ionic transference numbers have been measured in the ZrO 2-5.8%Y2O3-10%CeO2 system by open circuit Emf measurements involving different metal/metal oxide electrodes. In order to correlate the ionic transference number with grain size, high-density ceramic discs of different grain sizes (50 nm-5 μm) were prepared by sintering pressed powders at various temperatures and times. Hydrothermal synthesis was used to prepare nanocrystalline powders of the above material with uniform crystallite size (10 nm) and chemistry. Emf measurements on the samples suggested both ionic and electronic transport, the ionic transference number decreasing with increase in the grain size. This observation was attributed to an increase in the amount of continuous crystalline grain boundary phase in the ceramics as the grain size increased. The presence of crystalline silicate and zirconate phases in the grain boundary region was confirmed by electron microscopic imaging combined with microanalysis. In the large grain (5 μm) ceramics, the ionic transference number decreased linearly with temperature. As the grain size decreased, a maximum occurred in the ionic transference number vs. temperature curve. This maximum became more pronounced at smaller grain sizes. Better grain-grain contact and the doping effect of trivalent Ce in the grain boundary core are proposed to explain this observation.

Original languageEnglish (US)
Pages (from-to)221-232
Number of pages12
JournalJournal of Electroceramics
Volume10
Issue number3
DOIs
StatePublished - Jul 1 2003
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Condensed Matter Physics
  • Mechanics of Materials
  • Electrical and Electronic Engineering
  • Materials Chemistry

Keywords

  • Electron-ion transport
  • Grain boundary phase
  • Grain size
  • Transference number
  • ZrO-YO-CeO

Fingerprint Dive into the research topics of 'Electron-Ion Transport in ZrO<sub>2</sub>-Y<sub>2</sub>O <sub>3</sub>-CeO<sub>2</sub> Ceramics'. Together they form a unique fingerprint.

  • Cite this