Synthesis and characterization of La0.6Sr0.4Fe0.8Cu0.2O3-d oxide as cathode for intermediate temperature solid oxide fuel Cells

VAZQUES, S; DAVYT S; BASBUS J.F.; SOLDATI A.; AMAYA R; SERQUIS A,; FACCIO R; SUESCUN L.

JOURNAL OF SOLID STATE CHEMISTRY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2015

0022-4596

Nanocrystalline La0.6Sr0.4Fe0.8Cu0.2O3-d (LSFCu) material was synthetized bycombustion method using EDTA as fuel/chelating agent and NH4NO3 ascombustion promoter. Structural characterization using thermodiffraction dataallowed to determine a reversible phase transition at 425 °C from a lowtemperature R-3c phase to a high temperature Pm-3m phase and to calculatethe thermal expansion coefficient (TEC) of both phases. Importantcharacteristics for cathode application as electronic conductivity and chemicalcompatibility with Ce0.9Gd0.1O2-d (CGO) electrolyte were evaluated. LSFCupresented a p-type conductor behaviour with maximum conductivity of 135S.cm-1 at 275 °C and showed a good stability with CGO electrolyte at hightemperatures. This work confirmed that as prepared LSFCu has excellentmicrostructural characteristics and an electrical conductivity between 100-60S.cm-1 in the 500-700 °C range which is sufficiently high to work as intermediatetemperature Solid Oxide Fuel Cells (IT-SOFCs) cathode. However a change inthe thermal expansion coefficient consistent with a small oxygen loss processmay affect the electrode-electrolyte interface during fabrication and operation ofa SOFC.