Aqueous Fabrication of GO@High-Entropy LDH/SA-WPU Composite Fibers for Electromagnetic Wave Absorption

Fabric-based electromagnetic wave (EMW) absorbers have attracted widespread attention due to their favorable flexibility. However, most fabric-based EMW absorbers are manufactured via surface coating on conventional fabric substrates, which not only confines the EMW-absorbing behaviors to the fabric exterior but also poses potential environmental hazards with the involvement of organic solvents during production. In this work, a green strategy is proposed for producing intrinsic EMW-absorbing fibers through an aqueous process, with the senary high-entropy layered double hydroxide integrating graphene oxide (GO@SHE-LDH) as a functional constituent and the sodium alginate (SA)-waterborne polyurethane (WPU) dual-network system as a fiber matrix. The GO@SHE-LDH/SA-WPU (GLSW) fibers are woven into plain-weave fabrics, exhibiting a minimum reflection loss (RL_min) of -69.6 dB and a maximum effective bandwidth (EAB_max) of 7.1 GHz below 2.2 mm thickness, with favorable terahertz shielding/absorption performance (49.8 dB/45.6 dB) covering the 0.5-4.5 THz band, which is attributed to the synergistic EMW-absorbing effect of multiscale mechanisms. This work provides a promising eco-friendly method to produce functional fibers toward EMW absorption.