Preparation of Flexible Carbon Fiber Fabrics with Adjustable Surface Wettability for High-Efficiency Electromagnetic Interference Shielding

Abstract

In the 5G era, for portable electronics to operate at high performance and low power levels, the incorporation of superior electromagnetic interference (EMI) shielding materials within the packages is of critical importance. A desirable wearable EMI shielding material is one that is lightweight, structurally flexible, air-permeable, and able to self-clean. To this end, a bioinspired electroless silver plating strategy and a one-step electrodeposition method are utilized to prepare an EMI shielding fabric (CEF-NF/PDA/Ag/50-30) that possesses these desirable properties. Porous CEF-NF mats with a spatially distributed silver coating create efficient pathways for electron movement and enable a remarkable conductivity of 370 S mm–1. When tested within a frequency range of 8.2–12.4 GHz, this highly conductive fabric not only achieves an EMI shielding effectiveness (EMI SE of 101.27 dB at 5028 dB cm2 g–1) comparable to a very thin and light metal but also retains the unique properties of fabricsbeing light, structurally flexible, and breathable. In addition, it exhibits a high contact angle (CA) of 156.4° with reversible surface wettability. After having been subjected to 1000 cycles of bending, the performance of the fabric only decreases minimally. This strategy potentially provides a novel way to design and manufacture an easily integrated EMI shielding fabric for flexible wearable devices.

A Flexible Electromagnetic Interference Shielding Fabric Prepared by Construction of PANI/MXene Conductive Network via Layer‐by‐Layer Assembly

“…In this work, the higher SE A mainly depended on the perfection of the conductive network; while the SE R was caused by the interaction between incident microwave and mobile charge carriers. [36,37] Moreover, this multi-layer composite also demonstrated the promising potential in EMI shielding, as evidenced by the ultrahigh total EMI SE (≈60 dB) of the three-piece laminated PDMS/PMCFF-50 fabric (0.376 mm), as described in Figure 5f.…”

Polarization selection characteristics of carbon fiber orientation and interweaving for electromagnetic interference shielding behaviors

“…Consequently, for anisotropic fabrics, a mf is much less than the minimum value of isotropic fabrics (0.18). The a mf of anisotropic fabric #5 is 0.0004, which caused the high performance of EMI shielding in TM polarization according to Equation (18). Table 3 lists the various electromagnetic parameters of shielding materials containing carbon fiber fabrics obtained by this work and other studies in recent years.…”

“…Electromagnetic interference (EMI) shielding materials have attracted extensive attention in recent years [1][2][3] and have many forms, such as films, [4][5][6][7][8] composites, [9][10][11] foams, [12][13][14][15] fabrics, [16][17][18] etc. Among them, fabrics have developed into a research hotspot for EMI shielding materials due to their advantages of being soft, flexible, breathable, low cost and simple to prepare.…”

A Carbon Composite Film with Three-Dimensional Reticular Structure for Electromagnetic Interference Shielding and Electro-Photo-Thermal Conversion

“…Essential EMI shielding mechanism of the CFG film is indicated in Figure 3 c. The incident waves are initially reflected by the CFG film due to the discontinuity of impedance at their interface. Electromagnetic waves that enter CFG film are attenuated by either internal conduction path or multiple scattering in porous structure [ 20 ], both promoting the absorption loss of electromagnetic energy. This is consistent with the observation that SE A predominates over SE R .…”