The structural and electrical properties of samarium doped ceria films formed by e-beam deposition technique

Sm2O3-doped CeO2 (Sm0.15Ce0.85O1.925, SDC) thin films were formed by e-beam evaporation method. Thin films were formed evaporating micro powders (particle size varied from 0.3 to 0.5 mu m). The influence of deposition rate on formed thin film structures and surface morphology were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersion spectrometry (EDS), and atomic force microscopy (AFM). The deposition rate of formed SDC thin films was changed from 2 to 16 angstrom/s. The electrical properties were investigated as a function of frequency (0.1-10(6) Hz) at different temperatures (473-873 K). The formed SDC thin ceramic films repeat the crystallographic orientation of the initial powders using different substrates and different deposition rate. It was determined that crystallites size and samarium concentration are decreasing by increasing the deposition rate. The crystallites size decreased from 17.0 nm to 10.4 nm when SDC thin films were deposited on Alloy 600 (Fe-Ni-Cr), and decreased from 13.7 nm to 8.9 nm when were used optical quartz substrate. The best ionic conductivity sigma(tot) = 1.66 Sm-1 at 873 K temperature, activation energy Delta E-a = 0.87 eV (sigma(g) = 1.66 Sm-1, sigma(gb) = 1.66 Sm-1) was achieved when 2 angstrom/s deposition rate was used. The grain size (in the formed SDC thin films) was similar to 83 nm in this case. (C) 2016 Elsevier B.V. All rights reserved.