Fe₂O₃/PVDF-HFP nanocomposite: a study of dielectric behaviour and electromagnetic interference shielding performance in the X band frequency range

Iron oxide (Fe₂O₃)/Polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) nanocomposite film is investigated for its potential electromagnetic interference (EMI) shielding applications, particularly in the X-band (8–12 GHz) region. For this purpose, pure PVDF-HFP and Fe₂O₃/PVDF-HFP nanocomposite films are prepared by the solution casting technique. The prepared nanocomposite was investigated through various studies. The characteristic functional group peaks in the Fourier-transform infrared spectroscopy (FTIR) study confirm the successful incorporation of Fe₂O₃ nanoparticles into the polymer matrix of PVDF-HFP. The crystalline structure of Fe₂O₃/PVDF-HFP is revealed by the X-ray diffraction (XRD) data, which shows distinctive peaks of PVDF-HFP and Fe₂O₃ phases. The field emission-scanning electron microscopy (FE-SEM) images depict the homogenous dispersion of the Fe₂O₃ nanoparticles within the polymer matrix and the interaction between the Fe₂O₃ nanoparticles and the PVDF-HFP matrix. Further, at 50 Hz & 150 °C, the incorporation of Fe₂O₃ nanoparticles increased the dielectric constant of PVDF-HFP from 15 to 24, while the dielectric loss decreased from 4.3 to 2.4, resulting in a Q factor improvement from 0.4 to 0.55. Fe₂O₃/PVDF-HFP nanocomposite exhibits frequency and temperature-dependent impedance and AC conductivity, transitioning from insulating to conductive states. Cole–Cole analysis, in addition to dielectric loss tangent, impedance-matching, and attenuation constant evaluations based on complex permittivity, confirms multiple relaxation processes, good impedance matching, and improved internal attenuation in the X-band. The electromagnetic interference shielding effectiveness (EMI SE) studies in the X-band region indicate adequate shielding effectiveness of 8.55 dB. Therefore, Fe₂O₃/PVDF-HFP nanocomposite film provides preferable EMI shielding capabilities, indicating its potential applications in secure communication systems.