Wearable, fast-healing, and self-adhesive multifunctional photoactive hydrogel for strain and temperature sensing

Abstract

It is highly desired to synchronously impart wearable, fast-healing, and self-adhesive properties in the biocompatible photoactive hydrogel sensor response to strain and temperature for different practical applications. In this work, we designed a multifunctional polyvinyl alcohol (PVA) hydrogel with poly(dopamine)-modified carbon nanotubes (PVA/d-CNTs), which possesses a high self-healing efficiency of 83.08% within 5 s and strong adhesion to different substrates. Furthermore, the PVA/d-CNT sensor realizes full-range monitoring of human motion, with a broad strain range of up to ∼300%, and exhibits an impressive thermal response in human body temperature measurement for health information collection. In addition, the PVA/d-CNT hydrogel with controllable temperature property quickly heats up to ∼85 °C in 50 s under near-infrared laser irradiation, indicating a potential application in photothermal therapy. Finally, a wireless monitoring system for human motion detection and an alarm circuit for high-temperature warning were implemented in the PVA/d-CNT hydrogel sensor, demonstrating a promising potential application in multifunctional electronic skins, artificial intelligence, and intelligent robots.