LaSr ₃Fe _3-yCo _yO _10-δ (0 ≤ y ≤ 1.5) intergrowth oxide cathodes for intermediate temperature solid oxide fuel cells

LaSr ₃Fe _3-yCo _yO _10-δ (0 ≤ y ≤ 1.5) oxides with a perovskite-related intergrowth structure have been investigated as cathode materials for oxygen reduction reaction in intermediate temperature solid oxide fuel cells (SOFC). The electrical conductivity, oxygen vacancy concentration, and thermal expansion coefficient (TEC) increase with increasing Co content v. The electrocatalytic activity and power density measured with the LaSr ₃Fe _3-yCo _yO _10-δ/La _0.8Sr _0.2Ga _0.8Mg _0.2O _2.8 (LSGM)/Ni-Ce _0.9Gd _0.1O _1.95 (GDC) single cells with a porous Ce _0.9Gd _0.1O _1.95 (GDC) interlayer between the cathode and the electrolyte to avoid undesired interfacial reactions increase with increasing Co content because of an increase in the electronic and oxide ion conductivities of the cathode. The intergrowth LaSr ₃Fe _3-yCo _yO _10-δ cathodes offer electrochemical performances comparable to that of the well-known pervskite La _0.6Sr _0.4CoO _3-δ cathode but with an important advantage of significantly lower TEC.