Structural and electrochemical characterization of YBa(Fe,Co,Cu)2O5+δ layered perovskites as cathode materials for solid oxide fuel cells

Abstract Single- and double-doped YBa(Fe,Co,Cu)2O5+δ layered perovskites are prepared by solid state reaction method and their structural characteristics, thermal expansion coefficient, oxygen nonstoichiometry, electrical conductivity, and electrochemical performance are comparatively studied. The substitution of Co by Fe or/and Cu significantly improves thermal expansion properties as compared to undoped YBaCo2O5+δ. Electrochemical tests demonstrate the promising performance of synthesized materials as cathode materials at intermediate temperatures. Single doped YBaCuCoO5+δ cathodes reveal the lowest polarization resistance equal to 0.24 and 0.78 Ω cm2 at P(O2) P−1 = 0.2 at temperature of 800 and 700 °C, respectively.