Electrohydrodynamic printed programmable light-responsive MXene-cellulose/nanofiber-polydimethylsiloxane flexible actuators

Abstract

Abstract Flexible actuators have tremendous application potential in the fields of soft robotics, artificial muscles, electronic skins, and biomimetic actuation. However, MXene-based light-responsive flexible actuators face challenges such as nanosheet stacking, limited deformation modes, and difficulties in continuous motion control. To address these issues, an electrohydrodynamic (EHD) printing strategy was proposed for the fabrication of programmable MXene-cellulose nanofiber/polydimethylsiloxane (MXene-CNF/PDMS) actuators. The stacking of MXene nanosheets was effectively prevented by the ‘brick-and-mortar’ structure formed through hydrogen bonding. The MXene-CNF/PDMS actuator with the optimized mass ratio of 90 wt% MXene and 10 wt% CNF achieved a curvature of 2.34 cm −1 under near-infrared light at 550 mW cm −2 , improving performance by 31.5% compared to the MXene/PDMS actuator. The EHD printing method can achieve precise patterning design of the MXene-CNF layer by inducing multidimensional deformation through local thermal expansion stress mismatch. Actuators with MXene-CNF patterns fabricated via EHD printing along the 0°, 45°, and 90° directions exhibited multiple actuation modes, including vertical bending, spiral curling, and curling around the central axis. The application of EHD programmable printed flexible actuators in self-folding origami structures, light-driven wheeled robots, and biomimetic Archimedean spiral structures demonstrates the practical application of this method. This work establishes a collaborative innovation paradigm of materials, structure, and process, addressing the challenges of limited deformation modes and continuous motion control in flexible actuators, providing new solutions for complex movements in soft robotics.