Study of La 4 BaCu 5−x Co x O 13+δ series as potential cathode materials for intermediate-temperature solid oxide fuel cell

Abstract

La 4 BaCu 5−x Co x O 13+δ system was successfully synthesized by a modified Pechini route in air. A structural phase transition is observed along the series, from tetragonal ordered structure for 0 ≤ x ≤ 2 to a rhombohedral disordered perovskite for x = 5. A TEC value of 17.3 × 10 −6 K −1 , was found by High-Temperature X-ray Diffraction (HT-XRD) in air for La 4 BaCu 3 Co 2 O 13+δ . The conductivity of La 4 BaCu 3 Co 2 O 13+δ increases with temperature reaching a maximum of 778 S cm −1 at 405 °C in air followed by a decrease with further increase in temperature with values of 600–664 S cm −1 . The cathode polarization resistance of La 4 BaCu 3 Co 2 O 13+δ evaluated in air at 750 °C is 0.34 Ω cm 2 with an activation energy of 1.65 eV. These results demonstrate the possible use of La 4 BaCu 5−x Co x O 13+δ materials as cathode for Intermediate-Temperature Solid Oxide Fuel Cell (IT-SOFC).