Multifunctional EMI Shielding Aramid Nanofibers Films With Record‐Breaking Electrical Conductivity Enabled by Solid–Liquid Bicontinuous Conductive Network

ABSTRACT Developing electromagnetic interference (EMI) shielding materials that combine high shielding efficiency with electrical insulation for electronic packaging remains a critical challenge. In this work, multifunctional multilayer composite films comprising silver nanowires (AgNWs), liquid metal (LM), and aramid nanofibers (ANF) with a slippery surface (ALAFS) are fabricated via an integrated strategy of layered vacuum filtration, hot pressing, and scraper coating. With an optimized AgNWs:LM ratio of 2:1 and a loading of 60 wt.%, the AgNWs@LM/ANF films present a record‐breaking electrical conductivity of up to 2.1 × 10 4 S/cm. After coating the insulating layer, the ALAFS demonstrates an ultrahigh EMI shielding effectiveness (SE) of 92 dB and maintains excellent electrical insulation with a volume resistivity of 1.13 × 10 15 Ω·cm, effectively mitigating short‐circuit risks. The EMI SE remains superior (>90 dB) even under extreme environmental conditions. Furthermore, the ALAFS exhibits a high in‐plane thermal conductivity (λ) of 15.9 W/(m·K) for effective heat dissipation and robust mechanical properties with a tensile strength of 176 MPa. Synergizing surface hydrophobicity with the internal conductive network, ALAFS also offers efficient anti‐frost and de‐icing capabilities. In summary, ALAFS provides a comprehensive solution for the packaging and thermal management of next‐generation flexible electronics in complex environments.