Polarization Resistances of (Ln{sub}(1-x)Sr{sub}xCoO{sub}3 (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

摘要

This study focuses on cathode performances of (Ln{sub}(1-x)Sr{sub}x)CoO{sub}(3-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℃ ). (Ln{sub}(1-x)Sr{sub}x)CoO{sub}(3-δ) powders as cathode materials for IT-SOFC, which can be operated between 600℃ and 800℃ 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 (Ln{sub}(1-x)Sr{sub}x)CoO{sub}(3-δ)(Ln=Pr, Nd, Sm, and Gd, x=0, 0.3, 0.5, 0.7, and 1). Pr{sub}0.5Sr{sub}0.5CoO{sub}(3-δ) and Pr{sub}0.3Sr{sub}0.7CoO{sub}(3-δ) showed to 0.15 Ω cm{sup}2 of ASR at 700℃ and Nd{sub}0.5Sr{sub}0.5CoO{sub}(3-δ) to 0.14 Ω cm{sup}2 at 700℃. Sm{sub}0.5Sr{sub}0.5CoO{sub}(3-δ) showed the lowest ASR values of 0.10 Ω cm{sup}2 on 10% Gd-doped cerium oxide at 700℃.