Structural, dielectric and humidity properties of Al-Ni-Zn ferrite prepared by co-precipitation method

Highlights: • Al_0,2Ni_0,3Zn_0,5Fe₂O₄ nanoparticles have been fabricated by co-precipitation method. • Dielectric constant increase with increasing temperature and decreasing frequency. • The conductivity mechanism matches with the OLPT model. • The impedance decreases with increasing relative humidity for all test frequencies. Al_0,2Ni_0,3Zn_0,5Fe₂O₄ ferrite nanoparticles have been synthesized by chemical co-precipitation method and structural characterization has been analyzed using X-Ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis indicates that Al_0,2Ni_0,3Zn_0,5Fe₂O₄ ferrite nanoparticles crystallize in the cubic spinel phase. To determine the electrical properties of the sample, the real and imaginary parts of the dielectric constant have been investigated to a frequency range from 20 Hz to 10 MHz for 31 test frequencies. These measurements have been also repeated for different temperatures. The impedance analysis of the sample was carried out using Nyquist curves. The variation of the conductivity of the sample is also shown for the 31 test frequencies and the different temperature values in the range between 293 K and 733 K. The DC conductivity of the Al_0,2Ni_0,3Zn_0,5Fe₂O₄ as a function of temperature is also presented and the measurements confirm that the sample exhibits semiconductor behavior in accordance with the literature. Finally, the relative humidity, frequency and impedance map of the sample has been investigated in detail.