화학공학소재연구정보센터
Journal of Power Sources, Vol.171, No.2, 747-753, 2007
Structure and impedance spectroscopy of La0.6Ca0.4Fe0.8Ni0.2O3-delta thin films grown by pulsed laser deposition
Polycrystalline samples of La0.6Ca0.4Fe0.8Ni0.2O3 (LCFN) were prepared by the liquid mix process at 600 degrees C. The structure of the polycrystalline powders was analyzed with X-ray powder diffraction data. The XRD patterns were indexed as the orthoferrite similar to that of PrFeO3 having a single phase orthorhombic perovskite structure (Pbnm). LCFN films have been deposited on yttria-stabilized zirconia (YSZ) single crystal and polycrystalline substrates at 700 degrees C by pulsed laser deposition (PLD) for application to thin film solid oxide fuel cell cathodes. The structure of the films was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Both films are polycrystalline with a marked texture and present pyramidal grains in the surface with different size distribution. Electrochemical impedance spectroscopy (EIS) measurements of LCFN/YSZ single crystal/LCFN and LCFN/polycrystalline YSZ/LCFN test cells were conducted. The obtained ASR values at 850 degrees C for the single crystal and polycrystalline YSZ cell tests were 1.84 and 1.59 Omega cm(2), respectively. (C) 2007 Elsevier B.V. All rights reserved.