Flexible wearable sensors originating from ionogels have found extensive and significant applications in electronic skins, body-health monitoring, and personal healthcare diagnosis. Developing an ionogel-based sensor with robust mechanics and durable sensing in a wide service temperature range remains challenging. Herein, a high-performance wearable sensor with temperature-tolerant mechanics and durable sensing was constructed by virtue of hydrogen bonding between a poly(vinyl alcohol) (PVA)-incorporated nanocomposite interpenetrating network and an ionic liquid, i.e., 1-butyl-3-methylimidazolium iodide ([C 4 mim][I]). Through modulation of hydrogen bonding and thus good compatibility between [C 4 mim][I] and the network, the ionogels exhibited superior mechanics, excellent antifatigue, and durable sensing in a wide working temperature range. The ionogel-based wearable sensor exhibited stable and repeatable sensitivity toward various human motions including finger bending, elbow joint bending, and swallowing. More importantly, the pressure sensing can be completely preserved in a service temperature range of −20 to 80 °C. This work provided a feasible method to construct a mechanically strong, temperature-durable ionogel-based multimode sensor, which would find versatile applications as electronic skins, human-motion detection, and intelligent devices.

Ionogels have broad application prospects as flexible wearable materials owing to their desirable properties such as conductivity, stretchability, and adhesiveness. It is still challenging to integrate super adhesion, high self-healing capability, and stretchability into one ionogel sensor. Herein, an ionogel was conveniently constructed via one-step polymerization using acrylamide as the monomer and N,N′-methylenebisacrylamide as the cross-linking agent in 1-butyl-3-methylimidazolium chloride. The loosely chemically cross-linked network and affluent noncovalent interactions existed in the ionogel, i.e., double-ion hydrogen bonds and electrostatic interactions, act synergistically to endow the ionogel with super adhesion (up to 208 kPa to copper), high self-healing efficiency (up to 92.3%), excellent stretchability (up to 1977%), and good electrical conductivity (4.89 × 10–3 S/cm). The ionogel can be applied as a multimode sensor to monitor the strain, human movements, and pronunciation in real time. Considering its multifunctional properties and efficient preparation, the present study establishes an easy way for the rational design and fabrication of adhesive materials for wearable devices.

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