Reduction of electromagnetic pollution by the enhancement of microwave absorption of strontium hexaferrite functionalized poly (vinylidene fluoride) composite film

Strontium hexaferrite (SrH) nanoparticles were embedded in the matrix of PVDF by a simple and cost effective solution casting method to produce composite films suitable for the reduction of electromagnetic pollution. The influence of SrH nanoparticles on the structural, morphological, chemical, dielectric and microwave absorption properties of the SrH-PVDF composite films were also investigated in this report. X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) and Fourier transform infrared (FTIR) spectroscopy measurements were conducted to understand the improvement of the electroactive beta-phase of host PVDF due to the incorporation of SrH nanoparticles. Dielectric measurement of SrH-PVDF composite films in the GHz frequency range reveals that various polarization effects are present in the resultant composite films due to the formation of interfaces between the SrH nanoparticles and the PVDF matrix. High permeability of SrH nanoparticles and high permittivity of beta-phase improved polar PVDF in SrH-PVDF composite films play the most significant role to get the effective interactions with electromagnetic waves. Also, SrH nanoparticles in the PVDF matrix introduces various dielectric and magnetic losses, which were appeared due to the presence of induced electric dipoles, magnetic hysteresis, domain-wall displacement, exchange resonance and eddy current losses. In the present report the microwave absorption of all the composite films was measured and for the first time -106.9 dB and -109.9 dB at similar to 8.5 GHz microwave absorption were observed from these SrH-PVDF composite films. The overall improvement of the dielectric and magnetic responses of SrH-PVDF composite films make them the most potential candidate for the reduction of electromagnetic pollution from the device components operated in the field of microwave/GHz frequency range.