Lattice structure, sintering behavior and electrochemical performance of La1.7Ca0.3Ni1−xCuxO4+δ as cathode material for intermediate-temperature solid oxide fuel cell

Cu-doped La1.7Ca0.3NiO4+δ has been synthesized and evaluated as potential intermediate-temperature solid oxide fuel cell cathode materials. The effects of Cu substitution for Ni on lattice structure, sinterability, electrical and electrochemical properties of La1.7Ca0.3NiO4+δ are investigated. Cu-doping significantly enhances the sintering activity of La1.7Ca0.3Ni1−xCuxO4+δ. With increasing content of Cu, both the electronic conductivities and electrochemical performance remarkably increase, leading to an attractive cell performance. The increased conductivity may be related with the elongated Ni(Cu)O6 octahedron in perovskite layers while the decreased polarization resistance mainly correlates with the improved oxygen transport property induced by replacement of Ni by Cu. Single cell test suggests that La1.7Ca0.3Ni1−xCuxO4+δ is a promising candidate for solid oxide fuel cell cathode.