Robust conductive hydrogel advances self-powered intelligent sports monitoring and fair judging

Currently, combining multimodal perceptual ability with mechanical robustness poses a significant challenge for developing hydrogel-based flexible electronics. Herein, a robust conductive hydrogel was successfully synthesized by introducing cellulose nanocrystals (CNC) as nanofillers and lithium chloride (LiCl) as the conductive component into the copolymer network through a one-pot crosslinking procedure in a water-dimethyl sulfoxide binary solvent. Besides excellent stretchable, self-adhesive, anti-freezing, self-healing, and anti-swelling properties, tunable and reversible optical property was realized due to the polarity-induced microphase separation of the hydrophilic and hydrophobic group in the zwitterionic sulfobetaine chains, enabling cyclic information encryption and decryption. An all-weather wearable sensor array was thus developed for multi-modal sensing of various environmental stimuli, including mechanical, and thermal variations. Specifically, the intensity and spatial distribution of strain can be detected almost in real time within a broad strain range, thus realizing speech recognation, text-to-speech and human electrocardiogram signal acquisition and underwater non-contact sensing functions. Notably, the CPAMD-based triboelectric nanogenerator demonstrates impressive temperature tolerance (−40 °C and 60 °C), and remarkable material identification capability. A non-contact proximity sensing sensor and a foul detection system were thus developed by coupling the piezoresistive, triboelectric and capacitive sensing metrics to serve as an electronic referee for identifying foul in curling. This work provides a valuable reference toward combining excellent mechanical robustness with balanced electrical performance for tactile perception and intelligent sports monitoring.