Characterization, Production and Microwave Absorbing Properties of Polyaniline-NiFe2O4: Tb Composites

Abstract

In this study, terbium-doped NiFe2O4 was produced by using mixed oxide technique. The Ni1-xTbxFe2O4 composition was synthesized and x was selected as 0.025, 0.050 and 0.070, respectively. The single phase Ni ferrite was produced after sintering at 1250 °C for 4 h. X-ray diffraction (XRD), scanning Electron Microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were performed for the structural analysis. The results of the structural analysis indicated that second phase did not form in Ni1-xTbxFe2O4. Additionally, the polyaniline-terbium doped NiFe2O4 composites were produced by hot pressing using the compositions of Ni0.975Tb0.025Fe2O4.018, Ni0.950Tb0.050Fe2O4.037, Ni0.93Tb0.070Fe2O4.0525 and aniline. The weight ratios of terbium-doped nickel ferrite and aniline were 1:1 and 1:3 respectively and epoxy resin was used to produce microwave absorbing composites. The magnetic properties of fabricated composites were investigated using a vibrating sample magnetometer (VSM). The microwave absorbing performances of Polyaniline-NiFe2O4: Terbium composites were investigated by reflectivity in 0 – 8 GHz using two–port vector network analyzer. A minimum of – 39.41 dB reflection performance was obtained in 7.9 GHz at the thickness of 2.0 mm. This reflection performance can be modulated simply by controlling the content of polyaniline in the samples for the required frequency bands. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.20810

Keywords

• microwave absorber
• NiFe2O4
• polyaniline
• polymer-matrix composites
• reflectivity