Strong and continuous MXene/sodium alginate composite fibers prepared by immersion rotary jet spinning process with outstanding electromagnetic interference shielding performance

Recently, multi-functional MXene-based composite fibers have attracted much attention in fabricating smart textiles, owing to their outstanding electrical properties. However, the poor mechanical properties of such fibers usually make it difficult to spin continuously and limit their practical applications. Herein, a novel immersion Rotary Jet Spinning (iRJS) process was developed to produce high-strength continuous MXene/sodium alginate (SA) composite fibers (MSCFs). The prepared MSCFs exhibit superior fracture strength of 145.2 MPa and electrical conductivity of 479.2 S cm−1, with high MXene loading up to 75 wt%, respectively. In addition, they present linear-elastic and elastic–plastic behaviors, depending on the MXene content. The molecular dynamics simulation reveals that different tensile behaviors originate from the self-bending of SA chains and sliding between SA chains. Furthermore, one kind of non-woven MSCF felt structure was fabricated by a pressurized densification strategy. The electromagnetic interference (EMI) shielding effectiveness of this felt with a relatively thin thickness of ∼0.14 mm can reach ∼65.4 dB in the X-band. This work opens new avenues for fabricating high-performance multi-functional MXene-based hierarchical nanomaterials.