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The bulk structure, surface characteristics, catalytic properties, button cell performance, and stability of perovskite-type oxides with the formula Sr 1-x Ce xCo 0.2 Fe 0.8 O 3-d (x = 0.10, 0.15, and 0.20) were investigated as potential anode electro-catalysts for solid oxide fuel cells. In situ X-ray diffraction results indicated that the structural stability of the cerium-doped perovskites was enhanced with increasing cerium concentration. The catalysts with lower cerium concentration transformed from the initial cubic structure to a lower symmetry structure at high temperatures in a reducing environment. All the catalysts, however, were restored to the original cubic structure after re-oxidation. Electronic conductivity tests showed that the cerium-doped samples break down at higher temperatures, but display potential in terms of structural integrity and high conductivity at temperatures lower than 600°C. The new materials showed better performance than Ni-YSZ in catalytic methane oxidation tests. The sulfur tolerance is significantly enhanced with the cerium-doped perovskites, showing no deactivation for up to 10 h of operation under 50 ppm H 2 S. X-ray photoelectron spectroscopy analysis on the poisoned samples suggests that the sulfur may exist on the surface primarily as strontium sulfate. The sample with a cerium loading of 15 % (x = 0.15) showed a particularly high sulfur tolerance during chronoamperometry tests and its button cell performance matched well with that of Ni-YSZ anode. Sr 1-x Ce x Co 0.2 Fe 0.8 O 3-d (x = 0.10, 0.15, and 0.20) samples may have potential for low or intermediate temperature SOFC operation in which sulfur-containing hydrocarbon fuels are used, although they would not be stable at higher temperatures.

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