Abstract
Abstract
The rapid development of wireless communication networks and microwave devices has increased the requirement for dielectric materials with improved electrical performance and low dielectric loss at high frequencies. In the current study, NiO nanoparticles, ZnO nanoparticles, and NiO/ZnO nanocomposites were synthesized using a chemical precipitation method. The structural characteristics of the synthesized materials were investigated by X-ray diffraction (XRD), which confirmed the formation of cubic NiO and hexagonal ZnO phases. The crystallite sizes of NiO, ZnO nanoparticles and the NiO/ZnO nanocomposite were found to be 30 nm, 20 nm, and 14.47 nm, respectively. Nitrogen adsorption–desorption showed that NiO/ZnO nanocomposite exhibited a higher specific surface area 41.827 m² g⁻¹ compared with 32.71 m² g⁻¹ for NiO nanoparticles, improved surface properties due to the synergistic interaction between NiO and ZnO. High-resolution transmission electron microscopy (HRTEM) confirmed particle sizes of approximately 25 nm for NiO and 18 nm for the NiO/ZnO. Dielectric studies demonstrated that both the dielectric constant and dielectric loss decrease with increasing frequency due to reduced interfacial and space-charge polarization effects. Among all samples, the NiO/ZnO nanocomposite exhibited the lowest dielectric loss (≈ 0.30 at 10⁶ Hz) and higher AC conductivity. These enhanced electrical properties arise from strong interfacial interactions between NiO and ZnO, making the nanocomposite a promising candidate for high-frequency dielectric and electronic applications.