Cathodic overpotentials of Ln0.6Sr0.4Mn03(Ln = La, Pr, Nd, Sm, Gd, Yb, and Y) were studied for a new cathode of solid oxide fuel cell (SOFC). Cathodic overpotentials as well as the electrical conductivity strongly depended on the rare earth cations used for the A sites of perovskite oxide. Strontium doped PrMnO3exhibited the highest electrical conductivity among the examined perovskite oxide containing Mn for B sites. Moreover, overpotentials of Sr-doped PrMnO3cathode maintained low values in spite of decreasing the operating temperature. Consequently, almost the same power density of SOFC with La0.6Sr0.4Mn03cathode can be obtained at about 100 K lower operating temperature by using Sr-doped PrMnO3as the cathode. The overpotentials and electrical conductivity decreased and increased with increasing the amount of Sr dopant in PrMnO3, respectively, and the lowest overpotential was attained at x = 0.4 in Pr1-xSrxMnO3. Comparing with La0.6Sr0.4MnO3oxide, the reactivity of Pr0.6Sr0.4MnO3with Y2O3-stabilized ZrO2is much less than that of La0.6Sr0.4MnO3 and furthermore, the matching of thermal expansion of Pr0.6Sr0.4MnO3with Y2O3-ZrO2was satisfactorily high. Therefore, perovskite oxide of Pr0.6Sr0.4MnO3has a great possibility of the cathode materials for decreasing the operating temperature of solid oxide fuel cells.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry