This work demonstrates the enhanced EMI shielding performance of metal/carbon nanomaterials incorporated in a PVDF matrix with better electrical properties.

High performance electromagnetic interference (EMI) shielding materials with ultra‐low density, excellent flexibility with comprehensive nature are highly demanded for wearable electronics, aeronautic, industries, medical, and research facilities. To address these requirements, the metal‐carbon based polymer composites have been fabricated by simple and scalable synthesis techniques. Combining the effect of multiple scattering with absorption, a high shielding efficiency of up to 29 dB for 0.1 mm is achieved. Selective architects of Ag/Cu nanoparticles along with two‐dimensional conducting sheets of MWCNT/rGO form multiple scattering structures in poly(vinylidene fluoride) matrix, prepared by facile solvent cast technique. The paper discusses the preparation of the composites, studies on morphological aspects, and concludes with a study on EMI shielding in the frequency region between 8 and 12 GHz.

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Customization of substrates for the design of metamaterial absorbers gives the user a wide choice of parameters like flexibility, thickness, dielectric constant, etc. Polymer composites are attractive in this regard as they provide a variety of options to fabricate substrates with desirable properties depending on the matrix and filler materials. In this work, flexible polymer nanocomposites with different weight percentages of graphene nanoplatelets (GnP) in epoxy were fabricated and the dielectric characterization was performed. The presence of GnP increased the real part of the dielectric constant from 2.5 for 0 wt. % to 14.7 for 9 wt. % of the epoxy-GnP composites measured in X-band frequency. The substrate with 5 wt. % of GnP in epoxy having a relative permittivity of 7.3–j0.25 is chosen to design a metamaterial absorber, and the absorption studies are carried out numerically. The proposed absorber having a thickness of λ/22 is shown to have a maximum absorption of 99.8% at the frequency 9.88 GHz. Furthermore, an equivalent circuit model of the absorber is proposed and the analytical values of the circuit elements are determined. The metamaterial prototype is fabricated by coating metallic resonating structures on top of the flexible E-GnP5 substrate of thickness 1.4 mm by thermal evaporation. The performance of the fabricated absorber agrees well with the simulation results. These polymer nanocomposites with good flexibility, thermal stability, and optimum dielectric properties would be the future materials for developing conformal metamaterial absorbers for microwave applications.