Bioinspired Moisture-Driven Soft Actuators Based on MXene/Aramid Nanofiber Nanocomposite Films

Moisture-driven soft actuators are highly desirable in the fields of bionic robotics, artificial muscles, flexible electronics, etc. Here, a moisture-responsive actuator is fabricated by a mussel-inspired film structure composed of polydopamine-modified Ti3C2Tx MXene/aramid nanofiber (PDA-MXene/ANF) nanocomposites. The resultant actuator can be triggered by moisture and exhibits a large deformation (>360°) and high response speed (2 s) due to the remarkable hygroscopic performance of MXene. Moreover, the actuator exhibits a high tensile strength (374 MPa) and good toughness (12.3 MJ/m3). Several potential uses of the prepared nanocomposite film have been demonstrated, including biomimetic motion, electrical switches, crawling robots, and conceptual robotic arms. This bioinspired assembly strategy provides an approach for the development of high-performance moisture-driven soft actuators and expands the application of moisture actuator devices in soft robots by addressing the current shortcomings of the low strength and poor durability of MXene-based actuators.