Synthesis and Characterization of Rare Earth Doped Ferrite / Polyethylene Oxide Nanocomposites

Abstract

Nano-sized Li_0.5Ni_0.48Tb_0.02Dy_0.1Fe_1.9O₄ spinel ferrite nanoparticles were synthesized employing the micro-emulsion synthesis method. Polyethylene oxide was prepared through in-situ polymerization route. The ferrite-polymer nanocomposites have been synthesized by combining Li_0.5Ni_0.48Tb_0.02Dy_0.1Fe_1.9O₄ ferrite with polyethylene oxide polymer. Spectral, structural, morphological, and dielectric properties of the prepared nano-ferrite powders as well as nanocomposites were investigated by “X-ray diffraction analysis” (XRD), “scanning electron microscopy” (SEM), “Fourier transform infrared spectroscopy” (FTIR) and dielectric measurements. XRD analysis confirmed the synthesis of single-phase spinel structure only. The dielectric parameter was augmented with an increase of ferrite amount. FTIR spectra confirmed the existence of interactions between polyethylene oxide and ferrite particles. SEM study revealed that the nanocomposites comprised core/shell structure and inhomogeneous distribution of grain size. The dielectric parameters such as “real part of dielectric constant” (?), “imaginary part of dielectric constant” (?"), “tan loss”, “AC conductivity” and “quality factor” were investigated in the required range of frequency; that is, 1 MHz – 3 GHz. The peaking behavior has been observed for real (??) and “imaginary (???) parts of dielectric constant” and “dielectric loss” (tan?). “The peaking behavior” was detected beyond 1.5 GHz. A decrease in “the dielectric constants” and “dielectric loss” was found to with the increasing frequency. Dielectric parameters have been well elucidated by explaining “Debye-type relaxation model” in agreement with two layer “Koop's phenomenological theory”. The present investigated samples might have potential applications in high frequency.