Performance of Ni/ScSZ cermet anode modified by coating with Gd0.2Ce0.8O2 for a SOFC

A Ni/scandia-stabilized zirconia (ScSZ) cermet anode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd0.2Ce0.8O2) within the pores of the anode for a solid oxide fuel cell (SOFC). X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed in the anode characterizations. Open circuit voltages (OCVs) increased from 1.027 to 1.078 V, and the maximum power densities increased from 238 to 825 mW/cm2, as the operating temperature of a SOFC with 2.0 wt.%GDC-coated Ni/ScSZ anode was increased from 700 to 850 °C in humidified hydrogen. The coating of nano-sized Gd0.2Ce0.8O2 particle within the pores of the porous Ni/ScSZ anode significantly improved the performance of anode supported cell. Electrochemical impedance spectra (EIS) illustrated that the cell with Ni/ScSZ anode exhibited far greater impedances than the cell with 2.0 wt.%GDC-coated Ni/ScSZ anode. Consequently, 2.0 wt.%GDC-coated Ni/ScSZ anode could be used as a novel anode material for a SOFC due to better electrochemical performance.