Anodic reaction of dense Pd film in SOFC using Y-doped BaCeO3— Effect of mixed ionic conduction of electrolyte

The anodic reaction of a dense Pd film in a solid oxide fuel cell (SOFC) was investigated by using BaCe0.8Y0.2O3 − α (BCY) as an electrolyte. The anode performance of the film was better than the anode performances of porous Pd and Pt at 873 K. Although protons were predominant conduction in the porous Pt anode, oxide ion conduction and hole conduction slightly occurred in it at 873 K. In contrast, in the dense Pd film anode, small oxide ion conduction was compensated by hole conduction at 873 K. Hence, proton conduction occurred predominantly and hole conduction occurred to a small extent in it. However, at 1073 K, its performance decreased considerably because partial oxide ion conduction could not be inhibited by the dense Pd film. At the same temperature, conduction of oxide ions of BCY occurred predominantly in the porous Pt anode.