Lightweight and flexible Ni-deposited aramid fabric for electromagnetic interference shielding

Abstract

In this study, aramid nanofibers (ANFs) prepared from macroscopic aramid fibers were used as nano-coating materials, and the assembly of ANFs on aramid fabrics (AFs) was realized by layer-by-layer self-assembly (LBL) technology, resulting in AF@ANFs composite fabrics. This process effectively improved the surface chemical inertness of AF fabrics and increased the interfacial force between them and the coating. Subsequently, nickel nanoparticles (Ni NPs) were deposited on the surface of the AF@ANF composite fabrics by ultrasonic pretreatment combined with a palladium-free electroless plating process. This resulted in AF@ANFs@Ni composite fabrics with different Ni NP contents, exhibiting good coating adhesion strength. The electromagnetic shielding performance of AF@ANFs@Ni composite fabrics continues to improve with an increase in Ni NP content. When the concentration of NiCl₂ is 40 g L⁻¹, the block resistance of the AF@ANFs@Ni composite fabric is only 0.1 Ω □⁻¹, the conductivity is 138 205.0 S m⁻¹, and the shielding performance is as high as 100.5 dB. The environmental stability test shows that the composite fabric not only has good heat resistance, but also maintains a relatively complete structure in acidic, alkaline and salt environments, and good electromagnetic shielding performance. Without destroying the original fabric structure, the adsorption of ANFs not only increases the surface roughness of the AF fabric, but also improves the surface chemical inertness of the AF matrix, which proves that it is a modified material with good application potential.