Microstructural Characteristics of SDC Electrolyte Film Supported by Ni–SDC Cermet Anode

Abstract

As a promising electrolyte material for intermediate-temperature solid oxide fuel cells operated at a temperature of 600°C, a Sm0.2 Ce0.8 O1.9 (SDC) film supported by a Ni-SDC cermet anode was prepared through electrophoretic deposition. Detailed microstructural features of the electrolyte film were studied. In the region away from the interface, the microstructure of the SDC film is similar to that of the SDC bulk sample, containing nanosized domains embedded in a fluorite matrix. However, in the region near the interface, the diffusion of Ni from the cermet anode to the electrolyte film was observed with a depth of about 1 μm. Furthermore, the reduction in Ce and a high degree of oxygen vacancy ordering can be noticed in the interfacial region at the electrolyte side. It is suggested that these microstructural features could have negative impacts on the ionic conductivity of the electrolyte films. © 2009 The Electrochemical Society.