旋进式磁声双驱微/纳马达的构建及驱动特性研究

Micro/nano motors are tiny man-made machines that can be propelled by different mechanisms, including chemical propulsion,biological energy thrust and external stimuli guidance. They can preform various tasks during their movement, such as targeted payloads delivery, energy transportation,and information collecting, etc. In particular, procession micro/nano motor can perform more complex demanding tasks(e.g. drilling and adaptive adjusting) because they have rotational degree of freedom.Nevertheless, most of the existing procession micro/nano motors are propelled by single power, which significantly limited their applications. Additionally, precise motion control is another great challenge that scientists are currently facing. In regard to these issues, we will focus on the fabrication of procession micro/nano motors that can be driven by alternating magnetic and ultra-sound field simultaneously. In this project, the preparation of the motors involves several fabrication techniques, including photo-lithography, vacuum evaporation and solution-phase synthesis. The behavior of the micro/nano motors can be controlled by varying the parameters of the applied magnetic and ultra-sound fields, which offers the way for precise control in the applications. Furthermore,we will perform the quantitative theoretical studies on the behaviors of micro/nano motors propelled by magnetic and ultra-sound field, to understand the physics of powered movement on small length scales. Our research in principle may provide theoretical guides in designing, optimizing and manipulating the procession micro/nano motors.

微/纳马达是一类人工合成的微/纳米尺度的动力机器。它可将化学、物理或生物反应中的能量转换成机械功输出获取动力，从而实现在微小空间内的自主运动、物质输运、能量传递及信息采集等功能。旋进式微/纳马达具备除三维平动自由度以外的第四维旋转自由度，其相较常规微/纳马达可实现更为复杂的运动功能(如旋进破障、自适应调姿态)。然而，现有旋进式微/纳马达的单一驱动模式极大局限了其应用潜力与价值。此外，如何在微环境中实现对旋进式微/纳马达运动参量（如角加速度）的精准调控也面临着重大挑战。针对上述问题，本项目拟联合交变磁场和超声场两种驱动模式，采用光刻、蒸镀、液相合成等多技术手段构建旋进式磁声双驱微/纳马达，并通过外场诱导实现对马达驱动特性的精准调控，从而为深入发掘旋进式微/纳马达的应用潜力奠定基础。此外，我们还利用数值模拟技术定量研究马达的驱动机制与调控规律，以期为改善旋进式微/纳马达的驱动特性提供理论指导。

本项目聚焦研究旋进式磁声双驱微纳马达的设计、制备、性能调控与应用基础。三年来，项目组严格按照计划积极推进研究，取得了如下成果：(1). 分析了磁场与超声场联合驱动旋进式微/纳马达的动力学行为，基于此成功研制了一套微纳马达的磁/声双驱动平台; (2). 研制了一种介孔硅蠕虫状声/磁双驱微米马达，开展了其在细胞内药物运载与受控释放研究，证实了其良好的驱动性能与小分子药物运载性能；(3). 研制一种旋进式声/磁双驱Ni/Au纳米马达，开展了表面增强拉曼散射应用研究，结果显示其对拉曼分子的特征信号增强可达2个数量级；(4). 研制了一种仿百节虫磁性微米马达，在局域微区具备良好的机动能力与小载荷输运能力；（5）研制了一种可循环使用的硅基磁性阴阳马达，其表面具有多孔结构，可用于水体污染物清除。在本项目资助下，项目组在Small, ACS Applied Materal & Interface, Appl.Phys.Exp, Chin Phys B, J. Nanoscien. Nanotech, AIP Adv., Mater. Res. Exp.,等国际著名期刊发表论文10余篇，其中一区论文3篇；申请国家发明专利3项；培养了4名研究生；参加了10余次国际国内学术会议，报告了相应研究成果。本项目为新型微/纳马达研究提供理论基础、实验数据和应用新思路。