An Investigation on Structure, AC Conductivity, and Dielectric Characteristics of Ni_0.6Cu_0.2Zn_0.2Pd_3xFe_2-2xO₄ (x ≤ 0.1) Nanospinel Ferrites

Partially palladium (Pd) substituted Ni_0.6Cu_0.2Zn_0.2Pd_3xFe_2-2xO₄ (x ≤ 0.1) nano-spinel ferrites (NCZPd_x (x ≤ 0.1) NSFs) have been manufactured via sol–gel combustion route. The phase of all samples has been endorsed by XRD diffraction analysis. Their crystallite size (D_XRD) were estimated within 36–72 nm range. Morphology and the chemical composition have been confirmed by EDX (Energy Dispersive X-ray) and SEM-TEM (Scanning-Transmission Emission Microscopy) respectively. Complex impedance spectroscopy (CIS) was utilized to explore the dielectric characteristics within 20 to 120 ºC temperature and from 1 to 106 Hz frequency ranges. The two-dimentional frequency and temperature dependencies of the real and imaginary components of permittivity (ε^/ and ε^//), the dielectric loss tangent (tan(δ)), the real and imaginary parts of dielectric modulus (M^/ real and M^//), σ ac-conductivity (s), the real and imaginary components of impedance (Z^/ and Z^//), along with the experimental Nyquist diagrams Z^//(Z^/), were constructed and illustrated for all samples. The main feature of the frequencybehavior of the tan(δ) dielectric loss tangent is the presence of pronounced maxima depending on both frequency and temperature. The maximum value of the tan(δ) observed for the significantly doped x = 0.06-0.10 samples. The Pd substitution changes the electron relaxation and microwave absorption resonance.