Optimization of the electrical and dielectric properties of Zn-doped ferrites: Insights into the temperature-dependent behavior and applications in advanced electronics

This study investigated the role of zinc (Zn) substitution on the electrical and dielectric behavior of BaNi 1-x Zn x Fe 16 O 27 W-type hexaferrites for AC electrical conductivity (σ ac ), dielectric constant, and structure properties with (x = 0.0–2.0). High-purity oxides were blended and sintered by the ceramic process, and the measurements were carried out over the frequency range of 1–100 kHz and temperature range from room temperature to 500 °C using a Wayne Kerr 6500P LCR meter. The samples exhibited semiconducting activity, with σ ac increasing at elevated temperatures owing to the thermally activated charge carriers. The observed transition temperature for samples with x = 1.6 and x = 2.0 reflects a conduction mechanism transition shift, whereas the wide tan δ peaks at these levels disclose complex dielectric relaxation responses. In addition, the broad peaks in the tan δ, spectrum at these levels reveal the complex dielectric behavior and frequency-dependent relaxation processes. The behavior at x=1.6 and x=2.0, is an unrivaled combination of electrical conductivity and complex dielectric properties, which offers pathways for tailoring materials for high-temperature and frequency-sensitive applications. The single-phase W-type hexaferrite frame was verified through X-ray diffraction (XRD) analysis, with expanding lattice parameters as larger Zn 2+ cations replaced smaller Ni 2+ cations. Microstructural studies have shown that minimal grain growth and porosity increase with Zn content, which are characteristics that determine charge transportation, and polarization. Optimized behaviors were achieved for x = 0.4, with the maximum σ ac and ε′ and the lowest tan δ, proposed as a consequence of the optimal Fe 2+ /Fe 3+ hopping and polarization mechanisms. The results attest that Zn substitution efficiently tunes the structural, electrical, and dielectric parameters of BaNi 1-x Zn x Fe 16 O 27 ferrite and can be used for advanced applications as a superior material for radio-frequency and microwave devices, capacitors, materials innovation, and energy-storage applications.