Photocured Ti₃C₂T_x MXene/SiOC ceramic composite for electromagnetic interference shielding in the terahertz band

Terahertz (THz) electromagnetic interference (EMI) shielding materials with superior performance are urgently needed with the development of THz electronic devices. Herein, a photocured Ti₃C₂T_x MXene/SiOC ceramic (MSiOC) composite with a sandwich-like structure was prepared using a photosensitive resin as a precursor. In addition, the EMI shielding properties of the MSiOC composite with a low mass loading of the MXene were greatly improved. The influence of the content of Ti₃C₂T_x MXenes on the EMI shielding properties of the MSiOC composite was studied, and its EMI shielding mechanism was further elucidated. The resultant MSiOC composite exhibited an average shielding effectiveness (SE_T) of 24.5 dB in the frequency range of 0.2-1.6 THz at a MXene mass loading of only 0.3 wt%, which was remarkably improved by 53% compared to pure SiOC. In addition, the MSiOC composite with a broad high-absorptivity frequency band showed an absorption-dominated THz EMI shielding mechanism. This result proved that the synergistic effect of the MXene and SiOC was responsible for the high attenuation capability of MSiOC for THz waves. Finally, MSiOC with customized structures was easily fabricated via vat photopolymerization 3D printing, followed by a pyrolysis process. The smallest feature size of these structures was about 140 μm. Moreover, the flexible photocured green part could be secondary molded, which improved the structural controllability of the composite. Our work provides insights into the rational design of MXene-based composites for new-generation THz EMI shielding materials.