Preparation of Flexible Carbon Fiber Fabrics with Adjustable Surface Wettability for High-Efficiency Electromagnetic Interference Shielding.
Xiaokang MeiLongsheng LuYingxi XieYu-Xiang YuYong TangKwok Siong TehPublished in: ACS applied materials & interfaces (2020)
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.