Amphiphilic Block Copolymer Stabilized Liquid Metal Nanoparticles Induced Rapid Gelation of Highly Conductive, Adhesive, Anti‐Fatigue Hydrogel for Wearable Bioelectrode and Self‐Powered Sensor
Lijian Xu, Qiannian Yang, Lili Tang, Caifeng Li, Jianbo Fan, Tengfei Duan, Na Li, Maolin Yu, Jianxiong Xu
Abstract
Abstract Facile synthesis and achieving desired properties simultaneously in Eutectic gallium‐indium liquid metal (LM) implanted hydrogels are still challenging. Herein, highly conductive, adhesive, anti‐fatigue LM‐doped hydrogels are prepared by employing the amphiphilic block copolymer (PS‐ b ‐PAA) stabilized LM nanoparticles as both conductive filler and co‐initiator, which trigger the rapid gelation (<5 min) of 1‐vinyl‐3‐carboxymethyl imidazole bromide (IL) and acrylic acid (AA) monomers via polymerization at room temperature in the presence of borax crosslinked polyvinyl alcohol (PVA) and sodium chloride (NaCl), to form PVA/P(IL‐ co ‐AA)/NaCl‐LM hydrogels. The optimized hydrogel exhibits remarkable stretchability (702.84%), exceptional electrical conductivity (13.10 S m −1 ), robust interfacial adhesion strength (49.86 kPa), and a high fatigue threshold of 656.78 J m −2 (at 200% strain). Further, the hydrogels are used as wearable bioelectrodes to monitor tiny physiological signals, comparing favorably with commercial rigid electrodes. Moreover, the hydrogel‐based triboelectric nanogenerator (TENG) with high open‐circuit voltage (251.37 V) and outstanding fatigue resistance (15 000 cycles) can power common electronics. Besides, the TENG can also be used as self‐powered sensors to construct a sliding click communicator for aphasia and amyotrophic lateral sclerosis patients. This work provides a unique strategy for developing LM‐initiated self‐catalytic hydrogels with advanced properties toward wearable sensors for clinical healthcare.