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A composite anode composing of in-situ exsolved Fe Ni alloy (FNA) nanoparticles and Ruddlesden-Popper perovskite SrLaFeO 4 (SLF) substrate has been prepared by reducing La 0.5 Sr 0.5 Fe 0.8 Ni 0.20 O 3-δ (LSFN) perovskite precursor in humidified H 2 (3% H 2 O) at 800 °C. Roles of FNA and SLF, respectively, in performance and stability of the anode are systematically studied. The electric conductivity of the reduced LSFN and single cell performance of the composite (SLF-FNA) are examined in comparison with those of the SrLaFeO 4-δ (SLFO 4 ) anode alone. The significantly improved performance of the composite anode cell at lower temperatures (<700 °C) may be predominately ascribed to the enhanced electrochemical activity as well as electric conductivity due to the presence of FNA exsolution. The maximum power densities (P max s) of a single cell with the composite anode achieve 0.74, 0.58, 0.40, and 0.25 W cm −2 at 800, 750, 700 and 650 °C, respectively, which is comparable to the performance of Fe Ni-SDC cermets anode. However, the long time stability of the composite anode is superior to that of the Fe Ni-SDC cermets in various fuels, suggesting that SLF-FNA is sulfur-tolerant and coking-tolerant composite anode material, which possess great potentials for future application. The results can be used as guidance for designing high-performance composite anodes for intermediate temperature solid oxide fuel cells (IT-SOFCs). [ABSTRACT FROM AUTHOR]

A new cobalt-free perovskite oxide Pr0.5Sr0.5Fe0.8Cu0.2O3−δ (PSFC) has been synthesized and evaluated as cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The chemical compatibility of PSFC with Sm0.2Ce0.8O1.9 (SDC) electrolyte has be proven by XRD, and its electrical conductivity reaches the maximum value of 264.1 S cm−1 at 475 °C. Symmetrical cells with the configuration of PSFC/SDC/PSFC are used for the impedance study and the polarization resistance (Rp) of PSFC cathode is as low as 0.050 Ω cm2 at 700 °C. Single cells, consisting of Ni–YSZ/YSZ/SDC/PSFC structure, are assembled and tested from 550 °C to 800 °C with wet hydrogen (∼3% H2O) as fuel and static air as oxidant. A maximum power density of 1077 mW cm−2 is obtained at 800 °C. All the results suggest that the cobalt-free perovskite oxide PSFC is a very promising cathode material for application in IT-SOFC. [ABSTRACT FROM AUTHOR]