Programmable Wrinkled MXene-Based Soft Actuators with Moisture- and Light-Responsive Deformation and Water-Surface Locomotion Capabilities

Soft actuators are limited by single-mode driving technology, which poses challenges in dealing with complex and multidimensional movements. In this study, a multiresponsive soft actuator was fabricated by integrating a microwrinkling structure into an MXene-based film, enabling programmable motions. To achieve this, we introduced <i>n</i>-hexane into the film preparation process and utilized its rapid volatilization to accelerate the shrinkage difference between the film and the substrate. This resulted in anisotropic folding and excellent mechanical properties. Due to the remarkable moisture absorption and excellent toughness of MXene-based films, it exhibits rapid actuation in response to moisture gradients and light stimuli with large bending deformation, fast actuation speed, as well as excellent stability and durability. The anisotropic expansion and mechanical properties of the film enable it to have capability of three-dimensional shape-programmable configuration control. Furthermore, taking advantage of the exceptional photothermal properties of MXene-based films, we developed light-driven actuators that utilize the Marangoni effect for propulsion on the water surface, enabling programmable navigational control. Such a soft actuator has a broad applications prospect in the fields of biomimetic botanical models, terrestrial crawlers, and aquatic surface transport devices.