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

Double-perovskite YBa0.5Sr0.5Co1.4Cu0.6O5+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 La0.9Sr0.1Ga0.8Mg0.2O3−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 ×10−6K−1 between 30°C and 850°C in air. The lowest polarization resistance of 0.036Ωcm2 is achieved at 850°C. The maximum power densities of a single cell with the YBSCC cathode on a 300μm-thick LSGM electrolyte are 398mWcm−2 and 272mWcm−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.