Ln_(1-x)Sr_xCoO_3(Ln=Sm,Dy) FOR THE ELECTRODE OF SOLID OXIDE FUEL CELLS

摘要

The perovskite-type oxides were synthesized in the series of Ln_(1-x)Sr_xCoO_3)(Ln=Sm,Dy). The formation of solid solutions in Dy_(1-x)Sr_xCoO_3 was limited, compared with that in Sm_(1-x)Sr_xCoO_3. The electrical conductivities of the sintered samples were measured as a function of x in the temperature range of 30℃ to 1000℃. The highest conductivity of around 500S/cm at 1000℃ was found in Sm_(0.7)Sr_(0.3)CoO_3. The reactivity of all the samples with YSZ was examined at 800℃-1000℃ for 96h. The Sr-doped perovskite oxides were more reactive with YSZ and produced SrZrO_3 at 900℃ after 96h. However, no reaction product between SmCoO_3 and YSZ was observed at 1000℃ for 96h. The cathodic polarization of the oxide electrodes, sputtered on yttria stabilized zirconia(YSZ), was studied at 800℃-1000℃ in air. SmCoO_3 shows no degradation of the electrode performance at higher temperatures.