Freestanding Foils of NbSe₂ and Carbon Nanotubes for Efficient Electromagnetic Shielding

The presence of electromagnetic radiation is becoming an ongoing topic due to possible interference issues as well as potential health risks. Therefore, the development of electromagnetic interference (EMI) shielding materials is of utmost importance. Herein, a composite material for EMI shielding based on metallic niobium diselenide (NbSe 2 ) and single-walled carbon nanotubes (CNTs) with a low loading of 3 wt % is reported. The NbSe 2 + 3CNTs composite was prepared using a high shear-force homogenizer followed by vacuum filtration to obtain a freestanding foil with a thickness of 219 ± 22 μm. The EMI shielding effectiveness (SE) of the NbSe 2 + 3CNTs composite was also compared with its building blocks. The EMI SEs at 12.4 GHz were 31.4, 48.5, and 62.7 dB for pure NbSe 2, pure CNTs, and the NbSe 2 + 3CNTs composite, respectively. Such excellent performance of our composite material is attributed to a synergistic effect between the NbSe 2 and CNTs, where the CNTs not only increase the conductivity of the composite but also form an interconnecting network between the NbSe 2 sheets, thus forming a 3D network with abundant sites for EM wave attenuation. It is the first study on the EMI shielding performance of a TMD other than MoS 2 -based material.