An Investigation of LSF-YSZ Conductive Scaffolds for Infiltrated SOFC Cathodes. Issue 6 (24th March 2017)

• Record Type: Journal Article
• Authors: Cheng, Yuan; Oh, Tae-Sik; Wilson, Rachel; Gorte, Raymond J.; Vohs, John M.
• Is Part Of: Journal of the Electrochemical Society. Volume 164:Issue 6(2017)
• Page Start: F525
• Page End: F529
• Publication Date: 2017-03-24
• Subjects: Composite Scaffold -- Fuel Cell -- Infiltration -- Ionic Conductivity -- LSCF -- LSF -- Membrane -- SOFC -- YSZ; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0531706jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Porous composites of Sr-doped LaFeO3 (LSF) and yttria-stabilized zirconia (YSZ) were investigated as conductive scaffolds for infiltrated SOFC cathodes with the goal of producing scaffolds for which only a few perovskite infiltration steps are required to achieve sufficient conductivity. While no new phases form when LSF-YSZ composites are calcined to 1623 K, shifts in the lattice parameters indicate Zr can enter the perovskite phase. Measurements on dense, LSF-YSZ composites show that the level of Zr doping depends on the Sr:La ratio. Because conductivity of undoped LSF increases with Sr content while both the ionic and electronic conductivities of Zr-doped LSF decrease with the level of Zr in the perovskite phase, there is an optimum initial Sr content corresponding to La0.9 Sr0.1 FeO3 (LSF91). Although scaffolds made with 100% LSF had a higher conductivity than scaffolds made with 50:50 LSF-YSZ mixtures, the 50:50 mixture provides the optimal interfacial structure with the electrolyte and sufficient conductivity, providing the best cathode performance upon infiltration of La0.6 Sr0.4 Co0.2 Fe0.8 O3 (LSCF).