MXene/Cellulose Nanofibers Composite-Based Multiresponsive Soft Actuator for Programmable Soft Robots

Flexible actuators, as core components of soft robots, have attracted considerable interest for converting external energy into mechanical motion. However, most existing actuators still exhibit limitations in multistimulus responsiveness, shape programmability, and mechanical stability, which severely restrict their application in complex environments. Herein, we developed a multiresponsive, programmable bilayer actuator based on MXene/cellulose nanofibers (MXC) composite film and biaxially oriented polypropylene (BOPP) tape. By leveraging the hygroscopic, photothermal, and electrothermal properties of the MXC layer alongside the thermal expansion of the BOPP layer, the actuator achieves reversible, large-angle, and highly stable bending deformations under humidity, light, and electrical actuation. By combining pattern design and macroscopic reassembly strategy, various actuators that can realize programmable 2D-to-3D complex deformations have been demonstrated. As proof-of-concept applications, we have developed several soft robots, including a biomimetic leaf, a multiresponsive smart gripper, and a biomimetic crawling beetle robot, which hold significant potential for advancing next-generation soft robotics.