Bioinspired MXene-Based Soft Actuators Exhibiting Angle-Independent Structural Color

Area of Science:

• Materials Science
• Robotics
• Biomimetics

Background:

• Nature inspires advanced soft robots with structural coloration and actuation.
• Mimicking angle-independent color and shape-morphing of birds like the plum-throated cotinga is challenging.

Purpose of the Study:

• To create biomimetic soft actuators with angle-independent structural color and shape-morphing capabilities.
• To develop novel soft actuators for biomimetic soft robots and intelligent machines.

Main Methods:

• Fabrication of MXene-based soft actuators using controlled self-assembly of colloidal SiO2 nanoparticles onto aligned MXene films.
• Vacuum-assisted infiltration of polyvinylidene fluoride into the interstices for enhanced properties.

Main Results:

• Achieved brilliant, angle-independent structural color in the soft actuators.
• Demonstrated ultrafast actuation and recovery speeds (0.52 mm⁻¹ curvature in 1.16 s, 0.24 s recovery) in response to acetone vapor.
• Successfully demonstrated proof-of-concept applications including a gripper-like bird's claw, twining tendrils, and a fluttering butterfly.

Conclusions:

• The developed MXene-based soft actuators successfully mimic natural angle-independent structural color and shape-morphing.
• This strategy offers new insights for developing multifunctional soft actuators for somatosensory soft robotics.
• The findings pave the way for next-generation intelligent machines with advanced biomimetic functionalities.