Nanofiber-structured SSC-GDC composite cathodes for a LSGM electrolyte based IT-SOFCs

Nanofiber-structured Sm0.5Sr0.5CoO3-delta-Gd0.2Ce0.8O1.9 (SSC-GDC) composite cathodes prepared by infiltration of Gd0.2Ce0.8O1.9 (GDC) precursor solution into a porous Sm0.5Sr0.5CoO3-delta (SSC) nanofiber scaffold are investigated. The SSC-GDC composite cathode with the optimum infiltration load of GDC achieves interfacial polarization resistances of 1.609, 0.595, 0.209, 0.081 and 0.038 Omega cm(2) at 600, 650, 700, 750 and 800 degrees C, respectively. These polarization resistances are lower than those reported for comparable materials. Stable performance of the cathode is confirmed by testing at a constant current of 0.2 A/cm(2) for up to 100 h. Furthermore, the peak power density of a cell using the nanofiber-structured SSC GDC cathode in combination with a 650-mu m-thick La0.8Sr0.2Ga0.8Mg0.2O3-delta electrolyte is found to be 0.134 W/cm(2) at 800 degrees C. All of these results make of the nanofiber-structured SSC GDC composite cathodes a potential high-performance component for use in intermediate temperature solid oxide fuel cells. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.