Synthesis and Characterization of Mixed Spinel Ferrite Nanoparticles for EMI Applications

Abstract

There has been considerable interest in the properties of nanosized mixed spinel ferrites from an application point of view in the last few years. They are used in gas sensors, energy storage, microwave absorption, television, modems, computers, and as radarabsorbing material at lower frequencies. Mixed spinel ferrites with regulated compositions, crystal shapes, and sizes can be synthesized. This allows researchers to customize their features for specific purposes. It is possible to fine-tune the magnetic and electrical properties of materials by altering their composition. In the present work single phase and nanosized Nickel Zinc Cobalt Ferrite with composition NixZnxCo1-2xFe2O4 (x = 0.0, 0.1, 0.175, 0.25) synthesized by chemical co-precipitation method. The prepared samples were calcined at 600 0C for 2 hours. The structural properties were investigated by XRD, SEM, and FT-IR instrumental techniques. The X-ray diffraction pattern confirms the formation of a single-phase cubic structure of the composition, NixZnxCo1-2xFe2O4 (x=0,0.1,0.175,0.25). The average crystallite size calculated by using the Scherer formula from the XRD data was in the range of 10-14 nm. SEM images confirmed the agglomerated structure of mixed spinel ferrite nanoparticles. The FTIR analysis was used to investigate the octahedral and tetrahedral band locations. An impedance analyzer was used to investigate the samples' dielectric properties. The dielectric studies revealed the enhancement of dielectric constant, dielectric loss, and tangent loss. The AC impedance spectroscopy confirmed the resistance caused by the contribution of grain boundaries. The decreasing trend of impedance with the incorporation of Ni2+ and Zn2+ represents that conductivity increases in substituted samples which ultimately raise the absorption of EM waves. Using a vibrating sample magnetometer (VSM), the produced samples' saturation magnetization and coercivity were assessed. The saturation magnetization and coercivity values revealed a declining trend with increasing Ni and Zn content, according to the VSM study. The saturation magnetization at x=0.175 was increased to an ideal value of 73.49 emu/g. which makes it a potential candidate for EMI shielding applications in a highfrequency range.