Electronic and structural properties of La0.4Sr 0.6Ti1-yCoyO3±δ electrode materials for symmetric SOFC studied by hard X-ray absorption spectroscopy

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Federico Napolitano - , Comisión Nacional de Energía Atómica (Author)
  • Analía L. Soldati - , Comisión Nacional de Energía Atómica (Author)
  • Jochen Geck - , Chair of Physics of Quantum Materials, Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • Diego G. Lamas - , Universidad Nacional del Comahue (Author)
  • Adriana Serquis - , Comisión Nacional de Energía Atómica (Author)

Abstract

We present combined Synchrotron X-ray Absorption Near Edge Spectroscopy (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) study of La 0.4Sr0.6Ti1-yCoyO 3±δ (0 ≤ y ≤ 0.5), which are promising electrode materials for symmetric solid oxide fuel cells. The measurements were performed at room temperature at the Ti and the Co K-edges in order to determine the local structural and electronic changes around the two transition metals. We find that Ti remains in a higher formal valence (around 4+) independent of the Co concentration. In contrast to this, dramatic and systematic changes are observed for the Co as a function of y. We conclude that the stability of the Ti 4+ triggers the A-site deficiency in our samples and predicts that oxygen vacancies are much more easily formed at large Co content, which in turn will greatly enhance the performance as electrode material.

Details

Original languageEnglish
Pages (from-to)8965-8973
Number of pages9
JournalInternational journal of hydrogen energy
Volume38
Issue number21
Publication statusPublished - 17 Jul 2013
Peer-reviewedYes

External IDs

ORCID /0000-0002-2438-0672/work/159172170

Keywords