SOFCs for direct oxidation of hydrocarbon fuels with samaria-doped ceria electrolyte

Samaria-doped ceria (SDC) electrolyte-supported solid oxide fuel cells (SOFCs) with Cu-SDC and Cu-CeO2-SDC anode composites were fabricated. Current-voltage and impedance-spectroscopy measurements were used to characterize their performance at temperatures between 600 and 700degreesC. The cells demonstrated the ability to directly utilize not only hydrogen (H-2) but also dry butane (C4H10) fuel. At 700degreesC, the maximum power density of a cell with a Cu-CeO2-SDC anode composite was 246 and 170 mW/cm(2) for H-2 and C4H10 fuels, respectively. Impedance spectra suggested that for butane fuel, the anode resistance significantly limits the overall cell performance. It was shown that the addition of pure ceria to the anode significantly increased the catalytic activity for oxidation reactions and decreased the anode resistances. (C) 2003 The Electrochemical Society.