The influence of preparation technique on the grain size and electrical properties of CeO 2 /ZnO nanocomposites

Three different samples of CeO 2 /ZnO nanocomposites were prepared by two synthesis techniques. The first was prepared by a co-precipitation method and the other two samples were prepared by a sol–gel technique where one of them was synthesized by using propionic acid as a dispersing agent and the other one was prepared without a dispersing agent. XRD-spectra were studied and ensured that CeO 2 has a cubic structure where ZnO has a hexagonal phase. Moreover, the grain size of each synthetic sample was calculated by using Scherrer׳s equation. TEM images revealed that the average particle size of the first sample is the largest among the prepared nanocomposites and the other two samples have the lowest grain size and are nearly the same. The electrical properties such as direct current electrical conductivity σ dc , alternating current electrical conductivity σ ac , and dielectric constant were studied in the frequency range from 42 Hz to 1 MHz and temperature range from room temperature 25 °C to 250 °C.