Hu Siwei, Li Kexing, Nong Weijia, Liu Zhong-Wen, Liu Zhao-Tie, Zhan Yanhu, Jiang Jinqiang, Yang Peng, Li Guo
Key Laboratory of Syngas Conversion of Shaanxi Province, Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xian, Shaanxi, 710062, China.
School of Materials Science and Engineering, Liaocheng University, Liaocheng, 252000, China.
Adv Sci (Weinh). 2025 May;12(18):e2500669. doi: 10.1002/advs.202500669. Epub 2025 Mar 20.
Magneto-driven soft robots featuring remote and highly permeable controllability are considered promising, especially in biomedical and engineering applications. However, there is still lack of a high-precision method to regulate the distribution of magnetic fillers in polymer substrates, which severely limits the improvement of the actuating functionality. This work provides a photo-regulatable method to develop soft robots with locally distributed magnetic FeO nanoparticles. Solvent-casted polyvinyl alcohol/sodium carboxymethyl cellulose film is prepared as the substrate, and Fe ions are introduced to coordinate with carboxylate groups by surface treatment. Two processes, photo-reduction of Fe to Fe ions and the hydrolytic reaction of the two ions, are sequentially combined to in situ generate magnetic FeO particles. Spatiotemporal control of UV light irradiation determines the Fe/Fe ratio and, therefore the amount of generated FeO nanoparticles that decide magnetic field, NIR light, and moisture responsive actuating functionalities. Moreover, the external geometry of the composite can be tuned by inducing the formation of Al-carboxylate coordinates for strain retention, which enables shape programming of the composite to exhibit complex 3D-3D actuating behaviors. The proposed method enables the design and preparation of soft robots with spatially tunable magnetism and more advanced actuating behaviors.
具有远程和高渗透性可控性的磁驱动软机器人被认为很有前景，特别是在生物医学和工程应用中。然而，仍然缺乏一种高精度的方法来调节聚合物基质中磁性填料的分布，这严重限制了驱动功能的提升。这项工作提供了一种光调控方法，用于开发具有局部分布磁性FeO纳米颗粒的软机器人。通过溶剂浇铸制备聚乙烯醇/羧甲基纤维素钠薄膜作为基质，并通过表面处理引入铁离子与羧酸根基团配位。铁离子光还原和两种离子的水解反应这两个过程依次结合，原位生成磁性FeO颗粒。紫外光照射的时空控制决定了铁离子与亚铁离子的比例，进而决定了产生的FeO纳米颗粒的数量，这些纳米颗粒决定了磁场、近红外光和湿度响应驱动功能。此外，复合材料的外部几何形状可以通过诱导形成铝羧酸盐配位来调整以保持应变，这使得复合材料能够进行形状编程，以展现复杂的3D-3D驱动行为。所提出的方法能够设计和制备具有空间可调磁性和更先进驱动行为的软机器人。
