Structural, morphological and transport properties of nanostructured La1-Sr Co0.2Fe0.8O3- thin films, deposited by ultrasonic spray pyrolysis

摘要： The main aim of this study is to improve the electrochemical properties of LaFeO3-δ perovskite as cathode by strontium and cobalt doping in lanthanum and iron sites. Ultrasonic spray pyrolysis (USP) following sintering process in air was utilized to synthesize La1-xSrxCo0.2Fe0.8O3-δ (LSCF) with 0 ≤ x ≤ 0.4. X–ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and impedance spectroscopy techniques were used to study the structure, surface morphology and transport properties of the deposited films. Contrary to what might expect, up to x = 0.4, single orthorhombic phase of La1-xSrxCo0.2Fe0.8O3-δ have been obtained for all deposited films. Impedance spectroscopy results at intermediate temperatures (500–700 °C) indicated that by increasing of strontium, the conductivity increases, and activation energy decreases from 0.41 eV for x = 0–0.24 eV for x = 0.4.