Super anti-freezing, fast-responsive nanocomposite organohydrogels with excellent mechanical properties as multifunctional sensors for human motion monitoring

Conventional hydrogel sensors are always restricted in real applications due to weakness in mechanical properties, freezing and dehydration ability, as well as limited sensing functionality. Herein, a multifunctional nanocomposite organohydrogel is constructed by polyvinyl alcohol, tannic acid green reduction of graphene oxide with ethylene glycol-water (EG/H2O) binary solvent through a common freezing-thawing process to overcome the above challenges. The organohydrogel shows favorable stretchability (369%), tensile toughness (up to 1850.48 KJ/m3) and strength (tensile/compressive strength of 603 kPa/2181.63 kPa). Meanwhile, it exhibits a super anti-freezing (−133.7 °C) and moisturizing performance. As multifunctional sensors (strain/pressure/temperature sensors), it shows stable and sensitive detection in a large temperature range, and fast response (66 ms/5 ms as a strain/pressure sensor respectively). This high-performance multifunctional organohydrogel shows promising potential in flexible electronic devices, electronic skin and soft robots.