Tian Zhuangzhuang, Du Chuankai, Xue Jingze, Liu Yan
Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun 130025, P. R. China.
Key Laboratory for Cross-Scale Micro and Nano Manufacturing (Ministry of Education), Changchun University of Science and Technology, Changchun 130022, P. R. China.
Nano Lett. 2024 Oct 23;24(42):13422-13430. doi: 10.1021/acs.nanolett.4c04177. Epub 2024 Oct 10.
Optically and magnetically responsive soft actuators are gaining attention for their noncontact actuation, flexibility, and remote control capabilities. However, they face challenges in rapidly switching motion postures and modes, which limits their performance in complex environments. We developed bilayer hydrogel actuators based on poly(-isopropylacrylamide) (PNIPAm) using an ice-templating method combined with free radical polymerization. This approach results in the formation of large, interconnected pores within the hydrogel. Under near-infrared light (27 W/cm), the actuation speed of the actuator reached 38.5°/s, with complete recovery to the original shape 8 s after light cessation. In addition, the reversible changes in stiffness and volume enable the actuators to lock and dynamically adjust their magnetization curve, allowing for the decoupling of deformation and movement as well as the regulation of motion postures and modes. This work opens new pathways for multigait robots and shows promising applications in environmental monitoring and underwater exploration.
