One-dimensional Sr0.7Y0.3CoO2.65-δ nanofibers as cathode material for IT-SOFCs

One dimensional (1-D) Sr0.7Y0.3CoO2.65-delta (SYCO) nanofibers and nanofiber-based Sr0.7Y0.3CoO2.65-delta-Gd0.2Ce0.8O1.9 (SYCO-GDC) composites have been prepared and studied as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). 1-D SYCO nanofibers are synthesized by electrospinning technique and the subsequent calcination processes. X-ray diffraction (XRD) results indicate that 900 degrees C is adequate for the formation of phase pure SYCO, much lower than the temperatures adopted in other reported methods for SYCO synthesis. 1-D nanofiber-based SYCO-GDC composite cathodes have been fabricated by infiltrating the ionic conducting GDC phase into the porous SYCO nanofiber scaffolds, achieving interfacial polarization resistances of 0.651, 0.200, 0.057 and 0.011 Omega cm(2) at 600, 650, 700 and 750 degrees C, respectively, with an optimized SYCO:GDC mass ratio of 1:0.44. The stability of this SYCO-GDC (1:0.44) composite cathode was affirmed by 108-h constant current test. All these results suggest that 1-D nanofiber-based SYCO-GDC composite is a promising cathode material for IT-SOFCs. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.