Characteristics of Pr1-xMxMnO3 (M=Ca, Sr) as cathode material in solid oxide fuel cells

Calcium and strontium-doped praseodymium manganite powders were prepared as cathode materials in solid oxide fuel cells. The characteristics of these materials such as particle size distribution, electrical conductivity, cathodic polarization, thermal expansion, and reactivity with electrolyte were investigated. It was found that the optimum doping content of Ca and Sr was 30 mol% and that Ca-doped PrMnO3 had higher electrical conductivity and lower cathodic overpotential than Sr-doped PrMnO3. Further, the 30 mol% Ca-doped PrMnO3 had not reacted with Y2O3 stabilized ZrO2 (YSZ) in the temperature range 1000-1200 degrees C for 100 h and it had a thermal expansion coefficient close to that of YSZ. It was found that 30 mol% Ca-doped PrMnO3 was satisfactory for use as a cathode material in solid oxide fuel cells. (C) 1998 Elsevier Science S.A.