Preparation of CuO/CeO2 composites by the Pechini method and investigation of their structural and electrical properties

In this study, unary CuO and CuO/CeO2 composites with various contents of CeO2 were synthesized by the Pechini process. Transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction were used for structural characterizations. Impedance spectroscopy was also used to determine the resistance of grains and grain boundaries. The results showed that the CuO/CeO2 composites with the average crystallite size of 32 nm are successfully synthesized by the Pechini method, where cerium oxide particles are accumulated in grain boundaries. It was also found that the presence of CeO2 in the CuO/CeO2 composites increases the dielectric constant and decreases the dielectric loss, in comparison to pure copper oxide. Also, the optimum content of cerium oxide to attain the maximum dielectric constant was determined to be 2 wt%.