Stretchable, healable, adhesive, transparent, anti-drying and anti-freezing organohydrogels toward multi-functional sensors and information platforms

Abstract

Conductive hydrogels with moisturizing and freezing-tolerant properties have great potential applications in the field of flexible electronics because of their excellent flexibility and conductivity under harsh climatic conditions. Herein, we constructed a stretchable, self-healing, self-adhesive, transparent, anti-drying, and anti-freezing conductive organohydrogel by a simple one-step method. Owing to the designed double-network structures, multi-dynamic crosslinks and H₂O/DMSO binary solvent systems, the resulting organohydrogel demonstrates superior stretchability (2400% strain), prominent self-healing capability (1550% strain for the healed organohydrogel), outstanding anti-freezing property (below −50 °C), and excellent moisture retention (80% after 7 days). The as-assembled sensor based on this organohydrogel possesses a relatively high sensitivity (GF = 2.8) and a wide linear sensing range (0–1500%), ensuring the reliable and accurate monitor for various mechanical deformations and intricate human motions. Meanwhile, the fascinating features of organohydrogel sensors are that they can not only distinguish effectively the direction of human motions but also judge the temperature changes. More importantly, the pristine and healed organohydrogel sensors can still maintain their response functions even under an extremely low temperature of −50 °C, manifesting the superior capabilities to withstand mechanical damages and endure harsh climatic conditions. Interestingly, the as-prepared organohydrogel displays adjustable optical properties in different polar solvents and can serve as a dynamic information memory device for recording, erasing and encrypting information. This multifunctional organohydrogel may be a promising material applied in novel flexible electronics and information-recognition platforms in harsh environments.