Preparation and properties of La_0.6Sr_0.4Co_0.2Fe_0.8O₃-La₂NiO_4+δ composite cathode for IT-SOFC

Abstract

La_0.6Sr_0.4Co_0.2Fe_0.8O₃-La₂NiO_4+δ(LSCF-LNO) system was designed as the cathode material for IT-SOFC. No chemical reaction between the two constituents was detected in the binary system sintered at 1400°C. Among the LSCF-LNO system, 50 vol% LSCF-50 vol% LNO shows the relative density above 96% from 1200°C sintering and sufficient electrical conductivity of 157.7 S/cm at 800°C. This composition has moderate thermal expansion coefficient of 14.5 x 10^-6 K^-1 between 20 and 800°C for IT-SOFC and shows the polarization resistance of 1.05 Ω·cm² at 800°C.