Electrochemical behavior of LSCF/GDC interface in symmetric cell: An application in solid oxide fuel cells

摘要

In present paper, La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF)/Ce0.9Gd0.1O1.95 (GDC)/LSCF structure has been studied to understand electrode/electrolyte interface. The nanocrystalline powder required for screen printing was obtained through solution combustion synthesis with glycine as a fuel. The LSCF powder synthesized at fuel to oxidant ratio of two is calcined at 900 degrees C as TG-DTA reveals thermal stability only beyond 900 degrees C. The X-ray diffraction pattern of calcined powder demonstrates rhombohedral perovskite structured LSCF with 27 nm crystallite size. However, dynamic laser scattering shows 0.9 mu m sized agglomerates while TEM shows 74 nm particles. For potential application in solid oxide fuel cells, the temperature programmed reduction and oxidation were done on the LSCF. The results exhibit strong reduction and oxidation behavior around 860 and 388 degrees C, respectively. The cell with LSCF as an electrode shows minimum charge transfer resistance of 6.3 Omega cm(2) at 550 degrees C. (C) 2014 Elsevier B.V. All rights reserved.