A magnetically augmented eco-friendly conductive polymer composite for X-band electromagnetic interference shielding

Contemporary electronic device usage generates significant electromagnetic pollution, affecting nearby electronics and human health. Conventional shielding materials are inadequate, necessitating innovative solutions. This study developed a multilayered composite with iron(II, III) oxide (Fe₃O₄) nanoparticles, polythiophene (PTh) nanofiber arrays, and a gold nanolayer. The synergistic combination of magnetic nanoparticles and conductive polymer nanofiber arrays resulted in an electromagnetic interference (EMI) shielding effectiveness (SE) exceeding 30 dB in the X-band when Fe₃O₄ was used in moderate concentrations. This surpassed the EMI SE of a comparable composite prepared through a similar process but lacking Fe₃O₄ by approximately 10 dB. The enhanced EMI SE can be attributed to the magnetic nanoparticles, which introduced magnetic loss to attenuate electromagnetic radiation and improved the impedance match between the arrays and epoxy resin (EP) layers. Furthermore, the inclusion of nanoparticles enabled the material to exhibit an absorption-dominant EMI shielding mechanism, significantly reducing the secondary reflection of electromagnetic waves. Consequently, this novel eco-friendly EMI shielding composite shows promise for application in high-power electronic devices.