Ni-Sm_0.2Ce_0.8O_1.9 anode-supported YSZ electrolyte film and its application in solid oxide fuel cells

Ni-Sm_0.2Ce_0.8O_1.9 anode-supported YSZ electrolyte films were fabricated and a fuel cell based on this film was tested in this paper. The anode/YSZ film interface was investigated by means of SEM-EDX. The SEM results showed that the YSZ film was almost fully dense and crack-free. The analyses of EDX revealed that Ce and Sm cations preferential migrated from the NiO-SDC anode into the YSZ film for less than 3 μm while no significant diffusion occurred for Y and Zr. A cell of Ni-SDC/YSZ(14 μm)/LSM-YSZ was tested from 700 to 850 °C using humidified hydrogen as fuel and ambient air as oxidant. The cell provided maximum power densities of 304, 625, 980 and 1270 mW/cm² at 700, 750, 800 and 850 °C, respectively. Polarization analysis based on the impedance spectra showed that the anode polarization only accounted for 8% of the total electrode polarization while this ratio for cathode was 92%. A negligible anode polarization suggested that the diffusion of Ce and Sm and its negative effect on the performance of the cell were suppressed to an acceptable level in this study.