Structural and temperature dependent electrical conductivity propertıes of dy2o3–sm2o3 co-doped bi2o3

Abstract

In the present work, Dy2O3 and Sm2O3 double-doped Bi2O3-based materials are synthesized by exploiting the solid-state synthesis method. The structural and temperature dependent electrical properties of these ternary ceramic samples, which are candidate materials for solid oxide fuel cell (SOFCs) electrolyte, are determined by means of a powder X-ray diffractometer (XRD), the four point-probe method (FPPM), and the thermal-gravimetry/differential thermal analysis (TG/DTA). As a result of the XRD measurements, the fluorite-type fcc δ-phase with a stable structure is obtained for higher values of the dopant oxide material, which are the samples with the maximum content of fixed 20% Dy2O3 and 15% and 20% Sm2O3. The samples with the stable δ-phase structure have higher conductivities. The highest electrical conductivity is found for the (Bi2O3)0.6(Dy2O3)0.2(Sm2O3)0.2 sample, which was 2.5×10–2 (Ohm cm)–1 at 750 °C. The activation energies are also calculated from the Arrhenius charts, which were determined from the FPPM measurements. The lowest activation energy is found as 0.85 eV for the sample with the highest electrical conductivity.