Metal-supported Solid Oxide Fuel Cell with La0.4Sr0.6Co0.2Fe0.7Nb0.1O3-δ Cathode

Metal-supported solid oxide fuel cells (SOFCs) exhibited significant advantages, for example the superior mechanical strength, easy-processing and lower cost. In this paper, we report a new fabrication method for metal-supported SOFC single cell. The single cell with NiO and Fe₂O₃ (Ni:Fe=1:1) anode support, Gd_0.1Ce_0.9O_1.95 (GDC) electrolyte and La_0.4Sr_0.6Co_0.2Fe_0.7Nb_0.1O_3-δ (LSCFN) cathode was fabricated by traditional tape-casting, drop-coating, co-sintering and screen-printing techniques. Then the as-prepared single cell was reduced at 500, 600, 700 ^oC under 5%H₂-95%N₂. Results show that after treated the whole cell at 700 ^oC in the reducing atmosphere, the oxide support was mostly reduced into metal, while the LSCFN cathode maintained its perovskite structure. Then the cell performance was tested using humidified hydrogen, by comparison, the as-prepared cell without reduction was also tested. Electrical impedance spectroscopy tests were carried out with symmetrical LSCFN electrodes reduced at 500-700 ^oC. Results show that the polarization resistance lowered down with the reduction temperature increased, which may possibly due to the more oxygen vacancies created at higher reduction temperature. The fabrication method to reduce the whole cell is a promising way to fabricate the easy-processing metal-supported SOFC single cell.