Ultrathin Cellulose Nanofiber Reinforced Ti3C2Tx Crosslinked hydrogel for Multifunctional and Sensitive Sensors

Multifunctional strain sensors simultaneously satisfy all the requirements including flexibility, stretchability, biocompatibility and high responsibility to external stimuli are always in high demand for wearable electronics. In this work, we introduced modified bacterial cellulose nanofibers (BCNF) as double network hydrogel-reinforced substrates to prepare MXene-based strain sensor (MPCB). The well-percolated BCNF play important role to reinforce the polymer skeleton and induce the continuous MXene-MXene conductive paths. Consequently, the electrical conductivity was significantly improved and excellent mechanical properties were retained (with the elongation at break over 500%). The prepared hydrogel can act as a wearable sensor for human motion detection, including swallowing movements, finger bending, and wrist bending. They also exhibit promising applications with multiple characteristics, i.e., ideal EMI, adjustable flexibility, self-healing and self-adhesive performance. Our work provides a simple and practical strategy for a new generation of wearable electronic sensor devices.