A double perovskite decorated carbon-tolerant redox electrode for symmetrical SOFC

Abstract

Double perovskite Sr2MnMoO5+δ (SMM) based hybrid catalyst is synthesized with SrMoO4 (SM) nanoparticles' in-situ exsolution. And the super exchange model in double perovskite structure enable the excellent redox property of SMM based electrode. Electrolyte (Ce0.8Sm0.2O1.9, SDC)-supported symmetrical solid oxide fuel cell (SOFC) is prepared with the structure as SMM/NiO-SDC||SDC||NiO-SDC/SMM. The NiO-SDC powders are prepared from gel-casting combined co-synthetic method and SMM hybrid catalyst is loaded on NiO-SDC scaffold by solution infiltration. In-situ exsolved SM particles provide additional oxygen reduction reaction (ORR) active sites on electrode surface which also contributes to the cell's cathodic performance. The peak power densities of 245 and 183 mW/cm2 can be achieved by as-prepared electrode when operating in wet CH4 and C2H5OH fuels at 800 °C, respectively. And the cell runs stably for over 320 h with hydrocarbon fuel, which reveals SMM/NiO-SDC electrode's high electrochemical activity and promising carbon deposition resistance.