resumo
Conversion-electron Mossbauer spectroscopy analysis of model electrochemical cells, comprising porous (57)Fe-enriched (La(0.9)Sr(0.1))(0.98)Cr(0.6)Fe(0.3)Mg(0.1)O(3-delta) electrodes and lanthanum gallate solid electrolyte, showed no reductive decomposition of the perovskite electrode material in H(2)-containing atmosphere at 1073 K, even in the steam electrolysis regime. The predominant state of iron cations in the electrode surface layers was found to remain trivalent irrespective of the oxygen partial pressure in surrounding atmosphere and polarization, whilst oxygen coordination of Fe(3+) decreases on lowering electrode potential. (C) 2011 Elsevier By. All rights reserved.
palavras-chave
OXYGEN NONSTOICHIOMETRY; MIXED CONDUCTIVITY; ANODE MATERIAL; SOFC; TRANSPORT; MN; BA; LA; SM
categoria
Electrochemistry
autores
Tsipis, EV; Waerenborgh, JC; Kharton, VV
nossos autores
Vladislav Kharton
Investigador Principal CovidadoGrupos
Projectos
Novel layered ferrits materials with mixed ionic-electronic conductivity for applications in alternative energy sources (PTDC/CTM/64357/2006)
Novel methodological approaches to analyze ion transport mechanism in complex crystal lattices and to forecast performance-determining parameters of the oxide materials (PTDC/CTM-CER/114561/2009)
agradecimentos
This work was supported by the FCT, Portugal (projects PTDC/CTM/64357/2006, PTDC/CTM-CER/114561/2009 and SFRH/BPD/28629/2006).