Tailored Electro–Magnetic–Porous Multigradient Nanoarchitectonics for Absorption‐Dominated Electromagnetic Interference Shielding and Adaptive Multifunctionality
Runze Shao, Guilong Wang, Guilong Wang, Wenyu Wang, Jialong Chai, Guoqun Zhao, Guizhen Wang, Guizhen Wang
Abstract
Abstract Herein, a multifunctional electromagnetic interference (EMI) shielding membrane with a conductivity–permeability–pore size gradient structure is fabricated via shear‐induced in situ fibrillation coupled with layer‐by‐layer assembly. Under intense shear, carbon nanotube (CNT) nanofibers intertwine with polytetrafluoroethylene (PTFE) nanofibrils to form an interpenetrating dual‐nanofibrous network, which not only robustly anchors Fe 3 O 4 nanoparticles but also establishing continuous conductive and thermal pathways. Moreover, the integration of this unique dual‐nanofibrous structure with the intrinsic properties of its components endows the PTFE/CNT/Fe 3 O 4 ‐gradient (FCFe‐G) membrane with superior mechanical properties, superhydrophobicity, flame retardancy, and corrosion resistance. More importantly, leveraging a multigradient‐induced “impedance matching–multilevel polarization–reabsorption” synergistic mechanism, the FCFe‐G membrane (101.1 µm) achieves absorption‐dominated EMI shielding with an exceptional EMI shielding effectiveness (SE) of 53.79 dB and ultralow reflectivity (0.38). Furthermore, anisotropic thermal management and CNT‐driven negative temperature coefficient behavior facilitate rapid heat dissipation and early fire warning. The film's dual‐mode electro/photothermal response further enables aerospace deicing, medical hyperthermia, and antibacterial applications. This work introduces a “composition–structure multigradient” design paradigm, offering a promising strategy for intelligent EMI shielding in aerospace, flexible electronics, and smart wearables.