PVDF/MWCNTs-AgNWs@MXene bilayer 3 D networks electromagnetic shielding composite films with highly conductive

With the development of communication networks, wireless devices and aerospace industries. Electromagnetic wave hazards become prevalent. Therefore, it is essential to develop composites with better electromagnetic shielding properties. In this paper, highly conductive three-dimensional (conductivity up to 1.4×10⁴ S·m⁻¹) networked electromagnetic shielding composite films (Ti₃C₂T_x MXene-based functional composite films) were constructed using MXene (Ti₃C₂T_x), silver nanowires (AgNWs) and multi-walled carbon nanotubes (MWCNTs) in a bilayer. In particular, the aqueous solutions of 10 mL AgNWs and 15 mL Ti₃C₂T_x MXene were adsorbed on top of poly(vinylidene fluoride) (PVDF)/MWCNTs composite films by vacuum-assisted filtration (VAF), and the total electromagnetic interference shielding effectiveness (EMI SE_T) of the Ti₃C₂T_x MXene-based functional composite film was as high as 69.0 dB, which was 245% higher than that of the commercial standard (20 dB), of which the absorption loss effectiveness (SE_A) accounted for 85.1%. It is shown that the main electromagnetic loss mechanism of Ti₃C₂T_x MXene-based functional composite films is absorption loss, with a specific electromagnetic shielding effectiveness (SSE/t) of up to 2719.8 dB/(cm⁻²·g). This work provides structural design and research ideas for the application of novel MXene materials in electromagnetic shielding composites.