Effects of slurry composition on the electrolyte support structure and performance of electrolyte-supported planar solid oxide fuel cells

Yttria-stabilized zirconium oxide (YSZ) supports for planar solid oxide fuel cells (SOFCs) were prepared by the phase-inversion-assisted laser ablation technique. The effects of slurries with different 1-methyl-2-pyrrolidone (NMP) and polyethersulfone (PESf) contents on the structures of electrolyte supports were investigated systematically to determine the optimal structure. The slurry viscosity and porosity as well as the bending strength of the YSZ supports were measured. The electrolyte support with the optimized structure was selected to prepare three cells using different anode impregnation cycles. The results show that the YSZ support structure can be optimized effectively because the slurry composition significantly influences the slurry viscosity and therefore affects the electrolyte support structure. When the weight ratios of NMP/8YSZ and 8YSZ/PESf were 0.6 and 9.5, respectively, the electrolyte substrates possessed not only long finger-like pores throughout the section but also a strength of nearly 40 MPa and a porosity of approximately 45%. Based on the optimized YSZ supports, the prepared planar SOFCs delivered a peak power density of 203 mW cm⁻² at 800 °C after twenty cycles of Ni impregnation.