Multifunctional MXene-based composite films with simultaneous terahertz/gigahertz wave shielding performance for future 6G communication

Abstract

Wireless communication technology has reshaped the entire society in the past 20 years. Recently, many countries have started planning for sixth-generation (6G) communication, with an aim to provide services in the 2030s. Compared with 5G, 6G signals will use higher and wider frequency bands (both GHz and THz waves), and the application scenarios will be extended to various harsh environments (oceans and outer space), which poses great challenges for future 6G electromagnetic interference (EMI) shielding materials. In this study, we fabricated a multifunctional MXene/polyaramid composite film by hydrogen-bonding-induced self-assembly. Compared with those currently reported in the literature, this composite film exhibits three noteworthy advantages, and could be applied as a potential 6G EMI shielding material in the future. First, the composite film shows strong EMI shielding efficiency in both THz (52.7 dB@0.2–1.6 THz) and GHz (38.9 dB@8.2–12.4 GHz) bands with a low thickness of 20 μm. Second, high-density hydrogen bonding interactions between MXenes and polyaramids endow the composite film with excellent mechanical performance (493 MPa) and superior heat resistance (T_g > 260 °C and T_d > 520 °C). Third, the composite film displays outstanding durability in various harsh environments including high/low temperatures (−193–250 °C), rapid thermal shock (500 °C for 30 s), large-angle bending and acid/alkali/salt corrosion with its GHz/THz shielding performance and mechanical properties nearly unchanged. Besides, it is integrated with excellent Joule-heating performance with a remarkably high temperature output of 225 °C. Altogether, the composite films could be considered as promising 6G EMI shielding materials suitable for various harsh environment scenarios in the future such as Mars exploration and ocean mapping.