A comparison of Cu-ceria-SDC and Au-ceria-SDC composites for SOFC anodes

Solid oxide fuel cells (SOFC) with samaria-doped ceria (SDC) electrolytes were prepared with anodes made from either Cu, ceria, and SDC or Au, ceria, and SDC. These cells were tested in H-2 and n-butane fuels at 650degreesC. The similarity of performance (V-I) curves and impedance results for cells made with Au and Cu suggests that both metals are simply electronic conductors in the anode and that Cu does not play a catalytic role in direct-oxidation anodes made with Cu. The addition of ceria is shown to play an important role in improving anode performance, either through improved catalytic activity or mixed ion-electronic conductivity. (C) 2003 The Electrochemical Society.