Mono-dispersion decorated ultra-long single-walled carbon nanotube/aramid nanofiber for high-strength electromagnetic interference shielding film with Joule heating properties

High-strength, flexible, and multifunctional characteristics are highly desirable for electromagnetic interference (EMI) shielding materials to meet lightweight applications in the electric industry. Herein, we report a sustainable bioinspired double-network structural material connected by a hydrogen-bonded interface, that enables the creation of hybrid dual-networks benefiting from the mono-dispersion of aramid nanofibers (ANFs) and single-walled carbon nanotubes (SWCNTs). By directional filtration, the dual networks of the ANF/SWCNT composite films can be constructed into a laminated structure with preferential orientation during the stretching process, resulting in high fracture strength (113.45 MPa) and low breaking strain (<2%). Simultaneously, the as-prepared film delivers an adjustable electrical conductivity (131.9–798.57 S/cm), a remarkable EMI SE (43.01–75.28 dB), and high specific shielding effectiveness (SSE/t) of 1.281 × 104 dB cm2 g−1, which shows outstanding performance among the reported state-of-the-art SWCNT-based materials. More importantly, the films show excellent Joule heating performance with a fast thermal response (<15 s), a low driving voltage (0.5–5 V), and a wide temperature response range (89–445 °C). As such, the multifunctional composite films are considered as promising alternatives to a wide range of lightweight applications in electromagnetic shielding and thermal management.