Meticulous construction of asymmetric conductive networks in polyimide nanocomposite film for electromagnetic interference shielding

As electronic components trend towards miniaturization and integration, there is a growing demand for electromagnetic interference (EMI) shielding materials with anisotropy and excellent comprehensive performance. Here, a multifunctional flexible Polyimide-MWCNT-MXene nanocomposite film has been successfully fabricated based on a design strategy that couples conductive gradient and sandwich structure. The EMI shielding effectiveness of the high-performance film has been enhanced to 62.4 dB in the X-band and 46.1 dB in the terahertz band with the meticulous construction of asymmetric conductive network. Simultaneously, the nanocomposite film exhibits significant anisotropic EMI shielding with a shielding difference of 7.1 dB in the X-band and 5.2 dB in the terahertz band. The efficient synergistic design not only endows the film with good mechanical properties but also ensures remarkable stability under various extreme conditions. The film also displays multifunctionality, including thermal insulation and self-extinguishing properties. The proposed strategy offers a promising avenue for the fabrication of high-performance EMI shielding nanocomposites, which holds significant potential for applications in extreme environments.