Dry and Binder-Free Deposition of Single-Walled Carbon Nanotubes on Fabrics for Thermal Regulation and Electromagnetic Interference Shielding

Conductive textiles with good flexibility and durability are highly demanded for wearable electronics. However, the common approaches of making conductive textiles require multi-step solvent processes, which is tedious and environment unfriendly. Herein, the high-quality single-walled carbon nanotubes (SWCNTs), synthesized by the floating catalyst chemical vapor deposition method, were directed and dry coated on the melt-blown fabrics (MBFs) recycled from the waste masks with binder-free chemical. The obtained MBF/SWCNT composites displayed excellent conductivity and flexibility and thus can be further used as wearable and heatable textiles. The sheet resistance of MBF/SWCNT composites can be further reduced by gold chloride (AuCl3) doping from 57 to 26 Ω/sq. The electrical–thermal measurement showed that the pristine MBF/SWCNT composites can reach the surface temperature of ∼48 °C at a low voltage (5 V), whereas it increased to ∼110 °C after AuCl3 doping at the same voltage. In addition, the AuCl3-doped MBF/SWCNT film with a thickness of ∼150 μm displays a high electromagnetic interference shielding efficiency of 27.1 dB at the X-band. Also, the MBF/SWCNT composites displayed good stability after long-term heating, bending, and washing. Our multi-functional MBF/SWCNT textiles not only demonstrated the reusability of waste masks but also showed great potential applications in electromagnetic interference and heat management, such as thermotherapy pads and fast water evaporators.