Ni doped PrSr3Fe3O10-δ Ruddlesden-Popper oxide for active oxygen reduction cathode for solid oxide fuel cell

Abstract

PrSr3Fe3-yNiyO10-δ (PSFNO10, 0<y<0.2) was synthesized and investigated for the potential active cathode of a solid oxide fuel cell operating at low temperature. Effects of Ni substitution in PrSr3Fe3O10 on the structure, thermal expansion property, electrical conductivity, and cathodic performance of SOFC were studied. PSFNO10 has a tetragonal crystal structure with a I4/mmm space group. The unit cell parameter and crystallite size decreased when Ni was substituted at the Fe site. However, the electrical conductivity of PSFO10 was hardly changed by the addition of Ni and the dominant hole conduction was observed in PSFNO10 with and without Ni doping. The thermal expansion coefficient (TEC) was decreased by addition of Ni and the TEC was in good agreement with that of LSGM electrolyte. The power density of the single planar cell using PSFNO10 (Ni=10 mol%) cathode achieved the large power density of 679mW/cm2 and the cathodic overpotential was 131.3mV at 1.25Acm−2 at 1073K.