High performance dual strain-temperature sensor based on alginate nanofibril/graphene oxide/polyacrylamide nanocomposite hydrogel

Abstract The advanced wearable sensors are required to integrate the properties with prominent mechanical properties, superior sensitivity, and multiple stimuli sensing. Herein, a high performance dual strain-temperature sensor was designed based on alginate nanofibril/graphene oxide/polyacrylamide nanocomposite hydrogel. Alginate nanofibril network induced by salting-out provided the high energy dissipation and high ionic conductivity for the hydrogel, and graphene oxide endow the hydrogel with high thermal sensitivity. Owing to the multiple synergic effects, the hydrogel exhibited high-performance mechanical properties with superior stretchability of 3370% and high toughness of 8.87 MJ/m 3. The hydrogel presented a superior temperature sensitivity of 2.0%/°C, but also was also applied as a high-performance strain sensor with high gauge factor (GF=4.2), wide workable range (0.02–2000%), fast response time (~2.5 s) and long-time stability. Based on the good mechanical properties and high stimuli response to strain and temperature, the hydrogel sensor could be a potential candidate material for human-machine interaction, artificial prosthetics, and electronic interconnects.