Polarization Resistances of (Ln1−xSrx)CoO3 (Ln=Pr, Nd, Sm, and Gd x=0, 0.3, 0.5, 0.7, and 1) as Cathode Materials for Intermediate Temperature-operating Solid Oxide Fuel Cells

Abstract

This study focuses on cathode performances of (Ln1−xSrx)CoO3−δ (Ln=Pr, Nd, Sm, and Gd, x=0, 0.3, 0.5, 0.7, and 1) for intermediate temperature-operating solid oxide fuel cells (IT-SOFCs, 600–800°C). (Ln1−xSrx)CoO3−δ powders as cathode materials for IT-SOFC, which can be operated between 600°C and 800°C were synthesized by the glycine-nitrate-process (GNP) method. The impedance spectroscopy method was used to investigate area specific resistance (ASR) and electrochemical properties of (Ln1−xSrx)CoO3−δ (Ln=Pr, Nd, Sm, and Gd, x=0, 0.3, 0.5, 0.7, and 1). Pr0.5Sr0.5CoO3−δ and Pr0.3Sr0.7CoO3−δ showed to 0.15 Ω cm2 of ASR at 700°C and Nd0.5Sr0.5CoO3−δ to 0.14 Ω cm2 at 700°C. Sm0.5Sr0.5CoO3−δ showed the lowest ASR values of 0.10 Ω cm2 on 10% Gd-doped cerium oxide at 700°C.