Ordered to defect fluorite structural transition in Ce1-xNdxO2-δ system and its influence on ionic conductivity

U. Aarthi, Dhananjaya Shukla, S. Rengaraj, K. Suresh Babu*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

The structural transformation from fluorite – defect fluorite – hexagonal phase on the heavily doped ceria system (Ce1-xNdxO2-δ X = 0, 25, 50, 75 and 100 mol%) has been investigated in this study. The oxygen ionic conductivity increased with dopant content till 50 mol% due to the formation of rare earth C-type superstructure defect fluorite. The co-formation of rare earth C-type structure along with the fluorite increase the anion vacancies and facilitates the barrier free ion migration. The long-range ordering and the existence of mixed phases in the heavily doped (75 mol%) system lowered the oxide ion conductivity. Ce0.5Nd0.5O1.75 in disordered fluorite structure exhibits a superior ionic conductivity of 6.0 mS/cm with an activation energy of 0.93 eV which has a potential as electrolyte in solid oxide fuel cells application.

Original languageEnglish
Article number155534
JournalJournal of Alloys and Compounds
Volume838
DOIs
Publication statusPublished - Oct 15 2020
Externally publishedYes

Keywords

  • Ceria
  • Conductivity
  • Fluorite
  • Vacancy

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

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