Doped Perovskite Oxide, PrMnO ₃ , as a New Cathode for Solid‐Oxide Fuel Cells that Decreases the Operating Temperature

Cathodic overpotentials of Ln 0.6 Sr 0.4 MnO 3 (Ln is La, Pr, Nd, Sm, Gd, Yb, and Y) were studied for a new cathode for solid‐oxide fuel cells (SOFCs) with low overpotentials in a relatively‐low‐temperature region. Cathodic overpotentials strongly depended on the rare‐earth cations in the A sites of the perovskite oxide. In particular, overpotentials of a Sr‐doped PrMnO 3 cathode maintained low values despite decreased operating temperature. Consequently, almost the same power density of a SOFC with Ln 0.6 Sr 0.4 MnO 3 cathode was obtained at about 100 K lower operating temperature by using Sr‐doped PrMnO 3 as the cathode.