Microstructural stability of SSC fibrous cathode with embedded SDC particles for solid oxide fuel cells operating on hydrogen

Abstract

The research dealing with performance enhancement by Sm0.5Sr0.5CoO3-delta (SSC) fibrous cathode with embedded sm(0.2)Ce(0.8)O(1.9) (SDC) particles has been reported by our previous study. In this paper, in order to assess the feasibility and reliability of this fibrous SSC-SDC cathode as a practical cathode, we conducted the short-term stability test using a half-cell under cathodic polarization treatment to identify the degradation phenomena only at the cathode. The polarization treatment was conducted under the current density of 500 mA/cm(2). The stability test was carried out at 700 degrees C in air under the condition of open circuit. After the measurement, the resistance associated with charge transfer and surface catalytic reaction were increased by 159 and 77%, respectively. The reasons for this degradation can be considered common approaches of perovskites cathode materials such as grain growth and Sr-enrichment. Fortunately, the fibers maintain their original shape, porosity and interfacial adhesion to electrolyte.