Electrochemical behaviour of Ce0.9Gd0.1O2-δSOFC-anodes

In order to compare the electrochemical performance of Ce0.9Gd0.1O2-delta (CGO) in various fuels, impedance spectroscopy measurements were carried out in the atmospheres containing H-2, CO, CO2, CH4, N-2 at various compositions, in the temperature range 650degreesC to 850degreesC. Ohmic loss and polarization resistance were derived from impedance spectroscopy measurements. The stability at different temperatures of the anode was also investigated in 9%H-2/91%N-2 humidified with 3% H2O. The microstructure of the anode before and after degradation test was analysed by SEM. These investigations indicated similarities in the impedance and the activation enthalpies in hydrogen/water, methane/water and CO/CO2 atmospheres. No indications of methane cracking leading to carbon formation were found.