Hydrophobic wrapped carbon nanotubes coated cotton fabric for electrical heating and electromagnetic interference shielding

Abstract

Load conductive component onto textiles via coating method is a simple and facile fabrication process to prepare flexible smart wearable device. However, this functional textile will suffer a significant damage after washing or mechanical wear, which hindered its application. In this study, polydopamine (PDA) was used as an interfacial agent to enhance the combination between carbon nanotubes (CNTs) and cotton fiber to fabricated a highly conductive fabric. Furthermore, a hydrophobic material 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) was introduced to the conductive fabric via dip-coating process, which effectively fixed the CNTs and simultaneously realize the water resistance of the composite fabric, as the contact angle for the fabric was up to 138°. Owning to the formation of a stable conductive path, the composite conductive fabric always possessed a surface resistance lower than 110 Ω/sq. Even after going through the repeated mechanical deformation or multiple stripping cycles, this conductive pathway of the composite fabric was still well maintained. Benefit from the excellent stability and high electrical conductivity, this fabric shows an attractive electromagnetic (EMI) shielding performance, as its EMI shielding effectiveness was 22 dB under 6.57–9.99 GHz and 23 dB under 11.9–18 GHz. Furthermore, the fabric exhibited an outstanding electric heating performance with the heating temperature reaches more than 85 °C at 6 V. Along with the facile preparation technique and stable functional performance, we expect that this hydrophobic conductive cotton fabric can be used as wearable electronics and for the design of various smart flexible devices.