Direct methane solid oxide fuel cells, operated by supplying methane to a Ni/YSZ anode, suffer from degradation via accumulation of carbon deposits on the Ni surface. Coating a 40 µm thin film of La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 (LSCF) perovskite on the Ni/YSZ anode surface decreased the amount of carbon deposits, slowing down the degradation rate. The improvement in anode durability could be related to the oxidation activity of LSCF which facilitates oxidation of CH 4 and carbon deposits. Analysis of the crystalline structure of LSCF revealed that LSCF was stable in the reducing anode environment under H 2 and CH 4 flow at 750 °C and retained its perovskite structure throughout the 475 h long-term stability test.

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For the first time, a Fe-Ti-O containing pellet, a viable chemical looping particle, was used as a solid fuel for direct contact with the Ni/YSZ anode surface of a solid oxide fuel cell. A maximum power density of 97 mW cm À2 , corresponding to 84% of that in the H 2 fuel, was produced using Fe-Ti-O in an inert Ar gas environment at 750 C. The Fe-Ti-O pellets were able to generate stable electricity under repeated electrochemical oxidation and hydrogen reduction cycles. Temperature-programmed oxidationreduction coupled with infrared spectroscopic studies revealed that the oxidation of the Fe-Ti-O pellet followed a shrinking core model; the reduction followed a progressive-conversion model. The ability of the Fe-Ti-O pellet to generate electricity on the Ni/YSZ surface can be attributed to its low resistivity (<17 U cm) which allows electrons to transport from the electrochemical oxidation sites to the anode surface. This study demonstrates that coupling a SOFC with an external reducer using Fe-Ti-O, an oxygen carrier, is a good candidate for electricity generation.