A Ce/Ru Codoped SrFeO3?δ Perovskite for a Coke-Resistant Anode of a Symmetrical Solid Oxide Fuel Cell

摘要

Employment of identical oxides for the cathode and anode in a symmetrical solid oxide fuel cell (SSOFC) is beneficial for decreasing the fabrication costs of a robust cell. Ce doping on the A site of SrFeO_(3) increased the structural stability in a reducing atmosphere, but ceria was found to exsolve from the perovskite during the cooling process in the air if the doping level reached 20 atom %. The additional doping of 5 atom % Ru in Sr_(0.8)Ce_(0.2)FeO_(3) on the Fe site could prevent the ceria segregation in air and induce the surface decomposition under fuel conditions for the formation of nanoscale SrO, CeO_(2), and Ru~(0). The SSOFC with Ce/Ru codoped SrFeO_(3) on a Sr- and Mg-doped LaGaO_(3) electrolyte showed a small R _(p) value (0.12 Ω cm~(2)) when H_(2) and ambient air were used as fuel and oxidant, respectively. The peak power densities of 846 and 310 mW cm~(–2) were achieved at 800 °C using H_(2) and C_(3)H_(8) as fuel, respectively. The excellent coke resistance of the anode could be related to the simultaneous in situ exsolution of CeO_(2), SrO, and Ru~(0) nanoparticles.