Dual-Resolution Microstructural Analysis of Anisotropic Pore Structure in SOFC Anode Fabricated by Phase-Inversion Tape Casting

The phase-inversion tape casting technique is used for fabrication of Ni-YSZ anode substrate for solid oxide fuel cells to form anisotropic pore structures and hence to improve its gas transport property. Microstructure of the fabricated anode substrates is analyzed using the scanning electron microscope with dual resolutions: one at 10 µm scale to analyze the sponge-like pores and the other at 500 µm scale to analyze the anisotropic finger-like pores. Depth profile of the microstructural parameters is also obtained. SOFC cells are prepared with the anode substrates and their electrochemical performance is evaluated by the electrochemical impedance spectroscopy and compared with that of the conventional cell. The anode fabricated using the phase-inversion tape casting is found to have excellent gas transport property even at high current and diluted hydrogen conditions.