Synthesis, thermal, electrical and magnetic properties of Bi_0.6-xMn_0.5Ni_0.5Fe₂O₄ ferrite

A series consisting of six samples of Bi_0.6-xMn_0.5 Ni_0.5 Fe₂ O₄ spinel ferrites with different molar concentrations have been fabricated by using the facile co-precipitation method. (x= 0.0, 0.10, 0.20, 0.30, 0.40 and 0.50). The synthesized series structural properties and phase information are studied using XRD. FESEM is used to explore the surface morphology and EDS is used to characterize the composition of elements in the nanoparticles. Raman Spectroscopy of the synthesized samples confirms the five Raman active bands Raman spectra i.e. A₁g, Eg, and three belongs to T₂g. These five peaks are at 200, 318, 477, 560, and 684 cm^-1 indicates the successful confirms the formation of Bi_0.6-_xMn_0.5 Ni_0.5 Fe₂O₄ cubic nanoparticles. The vibrating sample shows a superparamagnetic character in magnetometry measurements. As the concentration of Bi is increased the saturation magnetization decreases from the value 82 emu/g. The graphs of TGA and DTA analysis showed weight losses with the rise in temperatures but no further weight loss was observed after 800°C and limits at 950°C. The dielectric measurements were performed between frequency ranges of 1MHz to 3GHz of the applied electric field. The dielectric parameters were observed to decrease by Bi substitutions whereas the particle size increases. This decreasing effect remains to continue by increasing the frequency. However, the resistance of the nanocomposite material is found to decrease. These dielectric parameters suggest that these nanocrystalline ferrites with the domino effect are suitable for microwave devices of GHz frequencies ranges.