LSGM-Carbonate Composite Electrolytes for Intermediate-Temperate SOFCs

LSGM(La0.9Sr0.1Ga0.8Mg0.2O3-δ)-carbonate composite electrolyte was prepared by molten salt infiltration method and its properties were analyzed by scanning electron microscope (SEM), X ray diffractometer (XRD) and A.C. impedance. LSGM-carbonate composite electrolyte showed the same phase patterns as pure LSGM which suggests carbonates exist in an amorphous state. SEM images of porous LSGM pellet indicated all of the pores are uniformly distributed and nearly all of them are connected with each other. The A.C conductivity measurements showed composite electrolyte possessed a much higher ionic conductivity than LSGM electrolyte at a temperature within the range of 450-650 oC. Conductive highways for oxygen ions and multi-ions conduction were employed in explaining the improved property of composite electrolyte.