Core-Sheath CNT@MXene Fibers Toward Absorption-Dominated Electromagnetic Interference Shielding Fabrics

Absorption-dominated electromagnetic interference (EMI) shielding fabrics are urgently needed to address the increasingly severe electromagnetic radiation pollution, especially the secondary radiation problem. In this study, we design novel core-sheath CNT@MXene fibers with a gradient conductive structure and corresponding fabrics to realize absorption-dominated EMI shielding performances. This coaxial structure utilizes carbon nanotubes (CNTs) as the sheath and MXene as the core and is constructed through a wet spinning technique. By virtue of the core-sheath structure, the conductive gradient structure in the fibers is easily optimized by adjusting the core MXene and sheath CNT content. This gradient conductive network of fiber effectively facilitates the incidence of electromagnetic waves and strong interactions between electromagnetic waves and the composites, resulting in excellent EMI absorption ability. Within the X-band frequency range, the fabric exhibits an electromagnetic interference shielding effectiveness of 23.40 dB and an absorption coefficient of 0.63. Due to the protection of polymer, the fiber's electrical conductivity remains stable under conditions such as multi-cycle bending, stretching, and ultrasonic treatment, and in high relative humidity environments. Additionally, the fabric also demonstrates EMI shielding stability in indoor environments. This work indicates the great potential of the gradient structured fibers to achieve an absorption-dominated mechanism for next-generation eco-friendly EMI shielding fabrics.