Water uptake and conduction in strontium ytterbium cerate

G. W. Coffey, L. R. Pederson, W. J. Weber

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Water uptake and conduction have been studied in SrYb 0.05Ce 0.95O 3-δ, a composition known to conduct protons, oxygen ions, and electrons, depending on temperature and environment. Water uptake kinetics evaluated by thermogravimetry occurred in two distinct stages: a rapid, initial weight gain (0.39±0.09 eV, attributed to grain boundary and near surface hydration) followed by a much slower uptake (2.8±0.4 eV, attributed to hydration of the bulk grains). From cyclic voltammetry and mass spectrometry measurements for a cell exposed to asymmetric conditions, currents and activation energies for electronic, oxygen ion, and proton conduction were determined. The activation energy for electronic conduction, 0.90±0.09 eV, is believed to be artificially high due to the increase in electron carrier concentration with increased temperature. The activation energy for oxygen ion conduction (0.97±0.10 eV) agrees well with other oxygen conductors. Proton conduction appeared to follow two different mechanisms: a low temperature process characterized by an activation energy of 0.42±0.04 eV, and a high temperature process, characterized by an activation energy of 1.38±0.13 eV. A possible explanation is that proton conduction at low temperatures is dominated by grain boundaries and is dominated by bulk conduction at higher temperatures.

Original languageEnglish
Title of host publicationMaterials Research Society Symposium - Proceedings
PublisherMaterials Research Society
Pages427-432
Number of pages6
Volume369
Publication statusPublished - 1995
Externally publishedYes
EventProceedings of the 1994 MRS Fall Meeting - Boston, MA, USA
Duration: 28 Nov 19942 Dec 1994

Other

OtherProceedings of the 1994 MRS Fall Meeting
CityBoston, MA, USA
Period28/11/942/12/94

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ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials

Cite this

Coffey, G. W., Pederson, L. R., & Weber, W. J. (1995). Water uptake and conduction in strontium ytterbium cerate. In Materials Research Society Symposium - Proceedings (Vol. 369, pp. 427-432). Materials Research Society.