Sr2Fe1+xMo1−xO6−δ as anode material of cathode-supported solid oxide fuel cells

In this study, perovskite-type oxides of Sr2Fe1+xMo1−xO6−δ (x = 0, 0.2, 0.35, 0.5) were synthesized and the phase stabilities both in oxidizing and reducing atmosphere were investigated. When calcined in the air atmosphere, pure perovskite phase can be obtained for the composition of Sr2Fe1.5Mo0.5O6−δ while a large portion of SrMoO4 second phase was detected in other compositions. Further reducing the above powders showed a pure phase for Sr2Fe1+xMo1−xO6−δ (x = 0, 0.2, 0.35) while minor amount of Fe was precipitated from the Sr2Fe1.5Mo0.5O6−δ. Due to the highest electrical conductivity and lowest polarization resistance of Sr2FeMoO6−δ, such composition has been applied as the cell anode for a cathode supported solid oxide fuel cell (CS-SOFC). Maximum power densities of 463 and 331 mW cm−2 have obtained for the fuel cell when measured at 800 °C using hydrogen and propane as fuel, respectively. The durability test in propane indicated that Sr2FeMoO6−δ could be a potential anode material with good tolerance ability toward coking formation.