Electromagnetic shielding fabric based on graphene layer-by-layer assembly improves the absorption and shielding performance

In order to alleviate the threats to human health caused by electromagnetic radiation, it is high time to focus on research into efficient electromagnetic interference (EMI) shielding material. Stainless steel blended (SSB) fabrics are widely used as EMI shielding products. However, they also present bottleneck issues, including poor electromagnetic wave absorbing performance and difficulty in further improving shielding effectiveness (SE). In this work, the electromagnetic SE and electromagnetic wave absorbing performance of SSB fabrics are enhanced by an improved layer-by-layer assembly method using graphene nanoparticles. The experimental results show that the SE of the fabrics is improved by up to 10 dB and becomes more stable after treatment with the improved layer-by-layer assembly method. In addition, the SE and electromagnetic wave absorbing performance of stainless steel/polyester/cotton blended fabrics are improved by increasing the mass fraction of graphene nanoparticles and the number of assembled layers. The SE is increased by up to 10.4 dB in the X- and K-bands when the mass fraction of graphene is 2.5 wt.%, and the number of assembled layers reaches five. The overall increase is about 5 dB. Furthermore, in the frequency range from 3 to 18 GHz, the effective absorption bandwidth reaches 3.6 GHz, and the minimum reflection loss (RL) is –27.5 dB at 14.8 GHz, which corresponds to 99.8% absorption of electromagnetic waves. The study confirms that this method can effectively enhance the SE and wave absorbing performance of SSB fabrics, providing a feasible strategy for designing absorption-based electromagnetic shielding products.