Ni-based cermet materials are typically used for anodes of solid oxide fuel cells. However, the Ni phase in such anodes can cause durability problems. One possible solution to the durability problems is to reduce the amount of Ni in the anode, although decreased Ni amount in turn reduces conductivity and electrochemical activity of the anode. In this study, Ni-SDC (samarium-doped ceria) cermet anodes were prepared with different SDC particle sizes and Ni contents, and it was investigated how particle size ratio of the SDC and Ni affected the performance at low Ni contents. AC impedance analyses revealed that ohmic resistance was the primary factor affecting the current-voltage characteristics in the tested system, and it was found that large SDC particles were effective in reducing the ohmic resistance even with low Ni contents. The behavior of measured ohmic resistances of the anodes was well described by percolation theory, indicating that the electrical conductivity of the anodes was governed by the formation of connected Ni clusters.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry