A Soft Robot Based on Charged Spiropyran Amphiphilic Supramolecular Nanoassembly for Macroscopic Actuation

Biomimetic motion has advanced soft robotic materials. Common photoresponsive polymeric materials can sustain soft actuating robotic functions, while supramolecular soft robotics provide unprecedented structural and functional roles, e.g., stimuli-responsiveness, intrinsic supramolecular dynamicity, and bioactive cell-material interfaces. However, the high structural requirements of hierarchical supramolecular assembly are crucial for the fabrication of supramolecular soft robotics, limiting its technological development. We demonstrate a generation of supramolecular soft robotics without high orientation order and structural uniformity, capable of sustaining macroscopic actuation. A highly charged supramolecular nanoassembly of spiropyran amphiphiles entraps water at the macroscopic state and releases water upon photoisomerization, resulting in macroscopic soft actuating robotic functions.