Development of electrolyte-supported intermediate-temperature single-chamber SOFCs using Ln0.7Sr0.3Fe0.8Co0.2O3-d (Ln = Pr, La, Gd) cathodes

I. RUIZ DE LARRAMENDI; D.G. LAMAS; M.D. CABEZAS; J.I. RUIZ DE LARRAMENDI; N.E. WALSÖE DE RECA; T. ROJO

JOURNAL OF POWER SOURCES

Elsevier

Año: 2009 vol. 193 p. 774 - 778

0378-7753

Iron-cobalt-based perovskite oxides with general formula Ln0.7Sr0.3Fe0.8Co0.2O3-d (where Ln = La, Pr and Gd) have been investigated for their application as intermediate temperature cathodes in SOFCS. Powdered samples of these materials were synthesized by a novel gel combustion process and then characterized by X-ray powder diffraction (XPD) and scanning electron microscopy (SEM). XPD patterns were satisfactorily indexed with an orthorhombic GdFeO3-type structure and, for all samples, a mean particle size of less than 1 ìm was estimated from the SEM data. Experimental Single-chamber SOFCs using with these materials as cathodes and NiO-SDC (samaria-doped ceria) and SDC as anode and electrolyte, respectively, were evaluated at 600C in a methane/oxygen mixtures. Peak power densities of 65.4, 48.7 and 46.2 mW/cm2 were obtained for Ag/Ln0.7Sr0.3Fe0.8Co0.2O3-d/SDC/NiO-SDC/Pt cells with Ln = Pr, La and Gd, respectively. The relatively high power density obtained for the Pr compound shows that it could be an interesting material for cathode of single-chamber SOFCs.