Synthesis of LSM–YSZ–GDC dual composite SOFC cathodes for high-performance power-generation systems

This article investigates a method in further improvement of a (La0.8,Sr0.2)MnO3 (LSM)-Yttria-stabilized zirconia (YSZ) dual composite cathode by adding material with high ionic conductivity such as gadolinia-doped ceria (GDC). A nano-porous composite cathode containing LSM, YSZ, and GDC was prepared by a two-step polymerizable complex (PC) method which minimizes the formation of YSZ–GDC solid solution. The structure of the resulting LSM/GDC–YSZ dual composite cathode was such that the LSM and GDC phases were present on the YSZ core particles without formation of the La2Zr2O7, SrZrO3, and GDC–YSZ solid solution. At 800 °C, the electrode polarization resistance of the LSM/GDC–YSZ dual composite cathode decreased to 0.266 Ω cm2, compared with 0.385 Ω cm2 for the LSM/YSZ–YSZ dual composite cathode. In addition, the Ni–YSZ anode-supported single cell using a LSM/GDC–YSZ dual composite cathode with H2 as the fuel achieved a maximum power density of 0.65 W cm−2 at 800 °C.