Solid oxide fuel cells supported on cathodes with large straight open pores and catalyst-decorated surfaces

The La0.6Sr0.4FeO3-δ-Gd0.1Ce0.9O1.95-δ (LSF-GDC) support with large straight open pores was formed by the phase inversion tape method, and used as a cathode for solid oxide fuel cells (SOFCs) comprising GDC electrolyte and Ni-GDC anode. La0.6Sr0.4CoO3-δ (LSC) nano-particles were deposited deeply inside the cathode using the impregnation method. The single cell with the LSC-modified cathode exhibited a maximum power density of 726 mW cm−2 at 750 °C, much higher than the one with the un-modified cathode (298 mW cm−2). The polarization resistance determined with the impedance spectroscopy was 0.025 Ω cm2 for the former, which was one order of magnitude smaller than that for the latter. It is concluded that the presence of large straight open pores in the phase inversion-derived cathode allows for easy impregnation of catalytically active nano-particles, enlarging the triple-phase-boundaries for oxygen reduction reaction and hence enhancing the electrochemical performance of the cathode-supported SOFCs.