Mechanically Robust, Antifatigue, and Temperature-Tolerant\nNanocomposite Ionogels Enabled by Hydrogen Bonding as Wearable Sensors

Abstract

Flexible\nwearable sensors originating from ionogels have found\nextensive and significant applications in electronic skins, body-health\nmonitoring, and personal healthcare diagnosis. Developing an ionogel-based\nsensor with robust mechanics and durable sensing in a wide service\ntemperature range remains challenging. Herein, a high-performance\nwearable sensor with temperature-tolerant mechanics and durable sensing\nwas constructed by virtue of hydrogen bonding between a poly­(vinyl\nalcohol) (PVA)-incorporated nanocomposite interpenetrating network\nand an ionic liquid, i.e., 1-butyl-3-methylimidazolium iodide ([C₄mim]­[I]). Through modulation of hydrogen bonding and thus\ngood compatibility between [C₄mim]­[I] and the network,\nthe ionogels exhibited superior mechanics, excellent antifatigue,\nand durable sensing in a wide working temperature range. The ionogel-based\nwearable sensor exhibited stable and repeatable sensitivity toward\nvarious human motions including finger bending, elbow joint bending,\nand swallowing. More importantly, the pressure sensing can be completely\npreserved in a service temperature range of −20 to 80 °C.\nThis work provided a feasible method to construct a mechanically strong,\ntemperature-durable ionogel-based multimode sensor, which would find\nversatile applications as electronic skins, human-motion detection,\nand intelligent devices.