| With respect to the use of thinner YSZ electrolyte and higher ionic conductivity electrolyte, the operation temperature of SOFC is significantly reduced, from 1000°C to an intermediate-temperature of about 600-800°C, which allows the use of metallic components to replace of their ceramic or cermet counterparts as the metallic interconnect and support of SOFCs. In this paper, efforts were paid to the Fe-Cr-xMn alloys and the preparation and characterization of Ni-supported SOFC. The oxidation kinetics of Fe-Cr-xMn alloys were investigated by the oxidation weight gain in cathode atmosphere. The phase constitution, microstructure, elements of oxide scales of Fe-Cr-xMn alloys were characterized by X-ray diffraction(XRD), scaning electron microscope(SEM) and energy dissipation spectroscopy(EDS), which showed that the the oxidation rate would increase with the increase of Mn content, as the formation of MnCr2O4 and Mn2O3. The electrical conductivity of Fe-Cr-xMn alloys were examed by the four probe way. The experimental results showed that electrical conductivity of the Fe-Cr alloys would increase as the addition of Mn element, however, the electrical conductivity would decrease with a higher content of Mn, which was caused by the oxides of Mn. In addition, in this study, a Ni-supported SOFC was successfully fabricated by tape casting and co-sintering. The porous Ni support was achieved from the reduction of NiO to Ni. The maximum power densities of the cell, measured at 700, 750 and 800 oC in a SOFC operating condition with humidified hydrogen on the anode side and oxygen on the cathode side are 0.316, 0.474 and 0.807 W cm-2, respectively. The AC impedance spectrum of the cell was also applied for the electrochemical characteristics of the cell.
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