Lin Guanhua, Wang Haifei, Lu Wensheng
Institute for Advanced Study Shenzhen University Nanhai Avenue 3688 Shenzhen Guangdong 518060 China.
Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Colloid Interface and Chemical Thermaldynamics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China.
Adv Sci (Weinh). 2021 Jan 29;8(6):2002672. doi: 10.1002/advs.202002672. eCollection 2021 Mar.
Nanodroplets have been paid great attention as they are crucial for a wide range of physical, chemical, and biological applications. In this paper, monodispersed nanodroplets are prepared and their directed motions are realized through conducting the formation of nonuniform structures via altering the ionic distribution within; all these dynamics have been observed by using in situ transmission electron microscopy liquid cell technology. It has been found that their transformation from random motion to directed motion is reversible. Moreover, combining multiple directed motions enables long-distance travel with directed motion taking up 95% of the total time. The results here also prove that aqueous nanodroplets can slide directionally on the hydrophilic surface like droplets sliding on hydrophobic surface. Furthermore, the authors successfully achieve the unidirectional transportation of in situ prepared Ag nanoparticles by using the nanodroplets as nanoreactor, carrier, and transporter. The size and number of as-prepared Ag nanoparticles can be quantitatively controlled. In summary, this research provides a new strategy for real-time generation and precise manipulation of aqueous nanodroplets. Together with the quantitatively controllable in situ synthesis of Ag nanoparticles within the nanodroplets, this work can prove their promising applications in many fields.
纳米液滴因其在广泛的物理、化学和生物应用中至关重要而备受关注。本文制备了单分散纳米液滴，并通过改变其内部离子分布来形成非均匀结构，从而实现了它们的定向运动；所有这些动力学过程均通过原位透射电子显微镜液池技术进行了观察。研究发现，它们从随机运动到定向运动的转变是可逆的。此外，将多个定向运动相结合能够实现长距离移动，其中定向运动占总时间的95%。本文的结果还证明，水性纳米液滴能够像液滴在疏水表面滑动一样在亲水表面上定向滑动。此外，作者利用纳米液滴作为纳米反应器、载体和运输器，成功实现了原位制备的银纳米颗粒的单向运输。所制备的银纳米颗粒的尺寸和数量能够得到定量控制。总之，本研究为水性纳米液滴的实时生成和精确操控提供了一种新策略。连同纳米液滴内银纳米颗粒的定量可控原位合成，这项工作能够证明它们在许多领域具有广阔的应用前景。
