High Toughness and Environmental Stability of MXene-Based Actuators for Flexible Wearable Devices

MXene-based actuators have attracted considerable attention due to their flexible stretchability, multistimulus responsiveness, and high sensitivity to external stimuli. However, the poor mechanical properties and relatively low environmental stability of MXene nanosheets significantly hinder their further development. Here, the design and fabrication of a highly tough and environmentally stable film for somatosensory near-infrared light-response actuators are reported. The excellent films are synthesized by vacuum-assisted filtration of cellulose nanofibers (CNF) and 3-aminopropyltriethoxysilane functionalized MXene nanosheets (S-MXene) and then self-assembled with a tape film. The bilayer actuator combines excellent environmental stability with tough mechanical properties and is capable of integrating real-time awareness and various exercise monitoring. The resulting actuator has advantages of excellent responsive speed (90° s^-1), good strain sensitivity (GF of 50.27), and high stability after many loading-unloading cycles at 8% strain. As proof-of-concept demonstrations, the bilayer film is applied for devising an intelligent device that can simultaneously detect human motion by real-time resistance signal feedback. This work is expected to provide new ideas to the design of a multifunctional somatosensory matrix with actuating and self-sensing performances and pave the way for the development of flexible wearable electronics via a built-in feedback signal.