Affiliation:
1. Key Laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province Institute of Applied Bioresource Research College of Animal Science Zhejiang University Hangzhou 310058 P. R. China
2. School of Materials Science & Engineering Zhejiang University Hangzhou 310027 P. R. China
3. Department of Biomedical Engineering The Chinese University of Hong Kong ShaTin Hong Kong SAR P. R. China
Abstract
AbstractDevelopment of stimulus‐responsive materials is crucial for novel soft actuators. Among these actuators, the moisture‐responsive actuators are known for their accessibility, eco‐friendliness, and robust regenerative attributes. A major challenge of moisture‐responsive soft actuators (MRSAs) is achieving significant bending curvature within short response times. Many plants naturally perform large deformation through a layered hierarchical structure in response to moisture stimuli. Drawing inspiration from the bionic structure of Delosperma nakurense (D. nakurense) seed capsule, here the fabrication of an ultrafast bi‐directional bending MRSAs is reported. Combining a superfine silk fibroin rod (SFR) modified graphene oxide (GO) moisture‐responsive layer with a moisture‐inert layer of reduced graphene oxide (RGO), this actuator demonstrated large bi‐directional bending deformation (−4.06 ± 0.09 to 10.44 ± 0.00 cm−1) and ultrafast bending rates (7.06 cm−1 s−1). The high deformation rate is achieved by incorporating the SFR into the moisture‐responsive layers, facilitating rapid water transmission within the interlayer structure. The complex yet predictable deformations of this actuator are demonstrated that can be utilized in smart switch, robotic arms, and walking device. The proposed SFR modification method is simple and versatile, enhancing the functionality of hierarchical layered actuators. It holds the potential to advance intelligent soft robots for application in confined environments.
Funder
National Key Research and Development Program of China
National Science Foundation
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry