Cerium-Cobalt-Copper oxides based SOFC anodes for the direct utilisation of methane as fuel

Solid oxide fuel cells – SOFCs – are capable of converting methane directly by internal reforming. New materials development aim to reduce the difficulties of fuel pre-processing by allowing the direct utilisation of anhydrous fuels. This avoids the addition of water, thus reducing system complexity and operational costs.
A CeO2-Co3O4-CuO based electrocatalyst powder synthesised by the amorphous citrate method has been investigated as SOFC anode for direct operation with anhydrous methane. The catalysts studied were characterised using X-ray diffraction (XRD) and thermogravimetric analysis (TGA).
Furthermore, electrochemical properties of the electrocatalyst were evaluated under hydrogen from 700 to 850°C, as well as with mixtures of anhydrous methane and hydrogen and also with pure methane as fuels at 850 and 950 °C. Composition was analysed with scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDX) at the anode material. In addition, coarsening observations were assessed on as-sintered pellet anode samples.
It was found that the Cerium-Cobalt-Copper oxide based materials are able to operate as anode electrocatalyst in SOFC whilst fed either with hydrogen or anhydrous methane as fuels. The utilisation of pure methane has shown to be a viable condition whilst operating above 800 °C. The eventual presence of carbon deposition was assessed by Raman spectroscopy.