Effects of dual porosity honeycomb structure in SSC-SDC composite cathode for SOFCs

This study proposed an effective structure for the cathode of SOFC to reduce resistance, the honeycomb structure with dual porosity (micro and macro pores). A Sm0.5Sr0.5CoO3−δ (SSC)-Sm0.2Ce0.8O2−δ (SDC) composite cathode for solid oxide fuel cells, with a noble honeycomb structure comprising of nano and micro-sized pores, was fabricated by electrostatic slurry spray deposition (ESSD). The macro-pores distribute in the whole film with size range of 5-20 μm and micro-pores were formed throughout the skeleton with the size under 1 μm. This dual porosity composite cathode from interface to surface of the electrode was deposited by electrostatic slurry spray deposition (ESSD). Its electrochemical property was evaluated using electrochemical impedance spectroscopy and turned out to be enhanced compared to a conventional porous structure of cathode. The polarization resistances were significantly decreased with increasing measurement temperature.