Peng Xia, Urso Mario, Ussia Martina, Pumera Martin
Future Energy and Innovation Laboratory, Central European Institute of Technology, Brno University of Technology, Purkynova 123, 61200 Brno, Czech Republic.
Department of Medical Research, China Medical University Hospital, China Medical University, No. 91 Hsueh-Shih Road, Taichung, Taiwan 40402, ROC.
ACS Nano. 2022 May 24;16(5):7615-7625. doi: 10.1021/acsnano.1c11136. Epub 2022 Apr 22.
Nature presents the collective behavior of living organisms aiming to accomplish complex tasks, inspiring the development of cooperative micro/nanorobots. Herein, the spontaneous assembly of hematite-based microrobots with different shapes is presented. Autonomous motile light-driven hematite/Pt microrobots with cubic and walnut-like shapes are prepared by hydrothermal synthesis, followed by the deposition of a Pt layer to design Janus structures. Both microrobots show a fuel-free motion ability under light irradiation. Because of the asymmetric orientation of the magnetic dipole moment in the crystal, cubic hematite/Pt microrobots can self-assemble into ordered microchains, contrary to the random aggregation observed for walnut-like microrobots. The microchains exhibit different synchronized motions under light irradiation depending on the mutual orientation of the individual microrobots during the assembly, which allows them to accomplish multiple tasks, including capturing, picking up, and transporting microscale objects, such as yeast cells and suspended matter in water extracted from personal care products, as well as degrading polymeric materials. Such light-powered self-assembled microchains demonstrate an innovative cooperative behavior for small-scale multitasking artificial robotic systems, holding great potential toward cargo capture, transport, and delivery, and wastewater remediation.
自然界呈现出生物体为完成复杂任务而进行的集体行为，这激发了合作型微纳机器人的发展。在此，展示了不同形状的赤铁矿基微型机器人的自发组装。通过水热合成制备出具有立方体形和胡桃状的自主运动光驱动赤铁矿/铂微型机器人，随后沉积铂层以设计出双面结构。两种微型机器人在光照下均表现出无燃料运动能力。由于晶体中磁偶极矩的不对称取向，立方体形赤铁矿/铂微型机器人能够自组装成有序的微链，这与胡桃状微型机器人所观察到的随机聚集情况相反。这些微链在光照下会根据组装过程中单个微型机器人的相互取向表现出不同的同步运动，这使它们能够完成多项任务，包括捕获、拾取和运输微尺度物体，如酵母细胞以及从个人护理产品中提取的水中悬浮物，还能降解聚合材料。这种光驱动自组装微链展示了小型多任务人工机器人系统的一种创新合作行为，在货物捕获、运输和递送以及废水修复方面具有巨大潜力。
