Laser-Induced Graphene/TiCN on a Polyimide/MXene Film as Interference Shielding Materials for Terahertz Electromagnetic Waves

High-performance electromagnetic interference (EMI) shielding devices for terahertz (THz) electromagnetic waves are vital for the next generation of electronics in the 6G era. Herein, we report the fabrication of smart THz EMI shielding devices based on TiCN nanoparticles and laser-induced graphene (LIG), which can be prepared by laser scribing a polyimide/MXene film. The laser-induced LIG/TiCN materials are porous and highly conductive, presenting an excellent capability of shielding the THz waves and infrared thermal response. The 80 μm LIG/TiCN material has a total shielding effectiveness (SET) of up to 30 dB in the wide frequency range (0.1–3 THz), which is attributed to the generation of TiCN nanoparticles and the related heteroatom interfaces with LIG. In addition, a multilayer sandwich structure is introduced into the LIG/TiCN shielding devices, which contributes to the impedance matching at resonance, hence, increasing the SET to 45 dB in the range from 0.5 to 1.5 THz. Furthermore, a sandwiched actuator consisting of PDMS, LIG/TiCN, and PI/MXene layers has been fabricated, showing a rapid response to infrared irradiation due to the outstanding photothermal effect of LIG/TiCN. Therefore, the laser-induced LIG/TiCN and the preparation strategy are promising for practical applications in EMI shielding and other electronics.