Characterization of Pr1−xSrxCo0.8Fe0.2O3−δ (0.2 ≤ x ≤ 0.6) cathode materials for intermediate-temperature solid oxide fuel cells

Cathode materials consisting of Pr1−xSrxCo0.8Fe0.2O3−δ (x = 0.2–0.6) were prepared by the sol–gel process for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The samples had an orthorhombic perovskite structure. The electrical conductivities were all higher than 279 S cm−1. The highest conductivity, 1040 S cm−1, was found at 300 °C for the composition x = 0.4. Symmetrical cathodes made of Pr0.6Sr0.4Co0.8Fe0.2O3−δ (PSCF)–Ce0.85Gd0.15O1.925 (50:50 by weight) composite powders were screen-printed on GDC electrolyte pellets. The area specific resistance value for the PSCF–GDC cathode was as low as 0.046 Ω cm2 at 800 °C. The maximum power densities of a cell using the PSCF–GDC cathode were 520 mW cm−2, 435 mW cm−2 and 303 mW cm−2 at 800 °C, 750 °C and 700 °C, respectively.