Abstract:
A series of Ni0.5Cu0.2Cd0.3Fe2-xAlxO4 (where x = 0.0 to 0.075 in step of 0.015) nanoparticles have been synthesized by sol-gel technique which are further annealed at 700oC. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) techniques have used to examine the structural and surface morphology of all produced materials. A vibrating sample magnetometer with an applied field of 1.5 T (in μ0H) is used to measure the magnetic (hysteresis) characteristics of these ferrite nanoparticles. Using a Wayne Kerr impedance analyzer and the two probe approach, the electrical and dielectric properties have examined in the frequency range of 20 Hz to 15 MHz. The electric conduction mechanism and the resistances at the grain boundaries in ferrite nanoparticles have studied using complicated impedance and modulus spectroscopy techniques. All samples have showed single-phase cubic spinel structures, according to XRD analysis, which shows peaks with greater sharpness and width. Scherrer's formula and FESEM data have used to calculate the crystallite sizes. On the other hand, the results of the Rietveld analysis have used to determine the cation distribution and other structural factors. Maxwell-Wagner space charge polarization and Koop's phenomena have used to explain the low-frequency dispersion behavior of dielectric properties and their consistency in high-frequency domain. It is worth mentioned that the conductivity phenomena show good agreement with dielectric behavior of the synthesized nanomaterials. Cole-Cole plot has used to separate the contribution of grain resistance and grain boundary resistance with observing the predominance of grain boundary resistance. Theories that already exist have used to discuss potential relationships between structural, magnetic, electrical, and dielectric properties.
