Composite Cathode Bi1.14Sr0.43O2.14-Ag for Intermediate-temperature Solid Oxide Fuel Cells

Composites consisting of strontium stabilized bismuth oxide(Bi 1.14 Sr 0.43 O 2.14 ,SSB)and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There were no chemical reactions between the two components.The microstructure of the interfaces between composite cathodes and Ce 0.8 Sm 0.2 O 1.9 (SDC)electrolytes was examined by scanning electron microscopy(SEM). Impedance spectroscopy measurements show that the performance of cathode fired at 700℃is the best.When the content of Ag 2 O is 70 wt%,polarization resistance values for the SSB-Ag cathodes are as low as 0.2Ωcm2 at 700℃and 0.29Ωcm2 at 650℃.These results are much smaller than some of other reported composite cathodes on doped ceria electrolyte and indicate that SSB-Ag composite is a potential cathode material for intermediate temperature SOFCs.