EMI shielding performance of PPy/Fe-WS2 nanocomposites in the Ku band

Abstract

Electromagnetic interference (EMI) poses critical challenges to human health and the performance of electronic devices, particularly with the proliferation of advanced technologies such as next-generation telecommunication networks, smart wearables, and electric vehicles. The growing reliance on wireless technologies necessitates ultrahigh-performance, cost-effective EMI shielding materials, focusing on absorption-based mechanisms. In this study, PPy/Fe-WS₂ nanocomposites were synthesized via in situ chemical oxidative polymerization, resulting in an agglomerated structure with well-integrated Fe-WS₂ within the polypyrrole matrix. These nanocomposites demonstrated exceptional microwave shielding performance within the Ku-band frequency range (12.4–18 GHz). The PPy/Fe-WS₂ nanocomposites with a 10 wt% Fe-WS₂ content demonstrated a remarkable electromagnetic wave attenuation of 99.7%, achieving a total electromagnetic interference shielding effectiveness (EMI SE) of 36.12 dB at 18 GHz. This shielding was primarily attributed to absorption (28.80 dB), with a smaller contribution from reflection (7.32 dB) with dielectric and magnetic loss values of 1.53 and 0.48 at 18 GHz respectively. The incorporation of Fe-WS₂ enhanced dielectric loss through the formation of conductive pathways, interfacial polarization, and relaxation processes, while Fe doping improved magnetic permeability, further augmenting the shielding performance. Additionally, the nanocomposite exhibited high AC conductivity (45.2 S m⁻¹), a reduced skin depth (0.82 mm), and a stable attenuation coefficient (1267.4), underscoring its effectiveness in EMI mitigation. These attributes establish the PPy/Fe-WS₂ nanocomposite as a promising candidate for satellite communication systems and other advanced applications requiring efficient and reliable EMI attenuation.