Ivy-Inspired Double-Spiral Gel Fibers with Multifunctional Sensing and Electromagnetic Interference Shielding Properties Toward Wearable Health Care and Monitoring

Abstract

Flexible sensors with multi-mode sensing capability are highly desired for wearable health monitoring; meanwhile, electromagnetic interference (EMI) shielding is also needed for the special health care of pregnant women and children. Herein, inspired by the helical structure of natural ivy, multifunctional double-spiral gel fibers are developed through a facial wet spinning-intertwining method. The conducting polymer-incorporated sodium polyacrylate polymer matrix serves as the adhesive and conductive hydrogel substrate, while different conductive fillers of carbon nanotubes (CNTs) and silver nanowires (AgNWs) are composited in each fiber for mutual synergistic effect. Due to the combined electrical conducting behaviors of CNTs and AgNWs, remarkable strain-sensing performance (sensitivity approximately 70.12) for single double-spiral fibers and effective EMI shielding property (total shielding effectiveness approximately 21.9 dB) for woven textiles are achieved. Because of differentiated triboelectric polarities of CNTs and AgNWs, the double-spiral fibers can also be used as a noncontact triboelectric nanogenerator sensor (sensitivity approximately -4.6 mV mm⁻¹). The practicality of the developed multifunctional double-spiral gel fibers is comprehensively demonstrated to detect various body joint and limb motions, monitor chest and wrist electrocardiogram signal, recognize nearby object material type with the help of artificial intelligence, and shield EMI from Bluetooth headset.

Graphical Abstract

Keywords

Double-spiral fibers / Hydrogels / Strain sensor / Noncontact triboelectric sensor / Electromagnetic interference (EMI) shielding

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Funding

Higher Education Institution Science and Technology Research Project of Hebei Province(JZX2024024)

RIGHTS & PERMISSIONS

Donghua University, Shanghai, China