Effect of calcination temperature on structural, magnetic, and dielectric properties of Mg_0.75Zn_0.25Al_0.2Fe_1.8O₄ ferrites

Abstract

Based on the desire to improve material properties, the effects of temperature have begun to be investigated. It was found that for nano-sized powder materials, such as ferrites, the structural properties like crystal structure and grain size, as well as many magnetic and electrical properties depending on them, change with the calcination temperature. Considering these changes, the effect of calcination temperature on the structural, magnetic, and electrical properties of MZA ferrites (Mg0.75Zn0.25Al0.2Fe1.8O4) prepared by co-precipitation was investigated in this study. The produced MZA ferrites were calcined at three different temperatures (600, 700, and 800 C-degrees). The X-ray diffraction results showed that the samples exhibited a cubic spinel structure. It was found that the crystal sizes (D_sch) calculated using the Debye-Scherrer equation increased with increasing calcination temperature (22.47, 33.53, and 42.53 nm). From the Williamson-Hall (W-H) plots, crystal sizes were calculated almost same as Debye-Scherrer crystal sizes. The nano-sized particles were examined by scanning electron microscope (SEM). Elemental analysis was performed using EDX. nu(1) and nu(2) absorption bands and O-H and C-H vibrations were detected in the FTIR spectra. Magnetic measurements were carried out at room temperature and in the range of +/- 60 kOe under the applied field. Magnetic results are explained by superparamagnetism. Dielectric measurements were performed at room temperature and a frequency range of 20 Hz to 10 MHz. The dielectric properties can be explained by Maxwell-Wagner theory. Impedance spectroscopy study revealed that the relaxation mechanism is consistent with the Cole-Cole model. In AC conductivity studies at room temperature, it was found that the sample calcined at 600 C-degrees would be suitable for energy storage devices.