Performance and life-time behaviour of NiCu-CGO anodes for the direct electro-oxidation of methane in IT-SOFCs

An anodic cermet of NiCu alloy and gadolinia doped ceria has been investigated for CH4 electro-oxidation in IT-SOFCs. Polarization curves have been recorded in the temperature range from 650 to 800 oC. A maximum power density of 320mWcm-2 at 800 oC has been obtained in the presence of dry methane in an electrolyte-supported cell. The electrochemical behaviour during 1300 h operation in dry methane and in the presence of redox-cycles has been investigated at 750 oC; variation of the electrochemical properties during these experiments have been interpreted in terms of anode morphology modifications. The methane cracking process at the anode catalyst has been investigated by analysing the oxidative stripping of deposited carbon species.