Performance of double-perovskite YBa0.5Sr0.5Co1.4Cu0.6O5+δ as cathode material for intermediate-temperature solid oxide fuel cells

Abstract Double-perovskite YBa 0.5 Sr 0.5 Co 1.4 Cu 0.6 O 5+ δ (YBSCC) is synthesized by the EDTA–citrate complexing method, and investigated as a novel cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs). There are no serious reactions between YBSCC and La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3− δ (LSGM) except a slight peak shift. The electrical conductivities of the YBSCC sample occurs a semiconductor–metal transition at about 350 °C. The thermal expansion coefficient (TEC) of the YBSCC sample is 16.4 ×10 −6  K −1 between 30 °C and 850 °C in air. The lowest polarization resistance of 0.036 Ω cm 2 is achieved at 850 °C. The maximum power densities of a single cell with the YBSCC cathode on a 300 μm-thick LSGM electrolyte are 398 mW cm −2 and 272 mW cm −2 at 850 °C and 800 °C, respectively. This study suggests that the double-perovskite YBSCC can be potential candidate for utilization as IT-SOFCs cathode.