Characterization, production and microwave absorbing properties of polyaniline-nife2o4: Tb composites

In this study, terbium-doped NiFe₂O₄ was produced by using mixed oxide technique. The Ni_1-xTb_xFe₂O₄ 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 Ni_1-xTb_xFe₂O₄. Additionally, the polyaniline-terbium doped NiFe₂O₄ composites were produced by hot pressing using the compositions of Ni_0.975Tb_0.025Fe₂O_4.018, Ni_0.950Tb_0.050Fe₂O_4.037, Ni_0.93Tb_0.070Fe₂O_4.0525 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.