An Shun, Zhu Mingyuan, Gu Kan, Jiang Modi, Shen Qingchen, Fu Benwei, Song Chengyi, Tao Peng, Deng Tao, Shang Wen
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
Nanoscale. 2020 Feb 21;12(7):4295-4301. doi: 10.1039/c9nr09575f. Epub 2020 Feb 6.
Discrete droplet transport has drawn much interest in a broad range of applications. Controlling the motion direction in droplet transport, however, is a long-lasting challenge. In this work, a simple yet efficient approach is demonstrated to realize the motion of droplets with directional control on nanostructured surfaces with predefined channels. Light is used as the external stimulus to induce the uneven thermal expansion of the substrate, which leads to the tilting of nanostructured channels so that the droplet is driven to move along the channel. Due to the easy manipulation of light, including both the light position and power density, this study demonstrates the controllable entrance of static water droplets into targeted channels and the simultaneous control of the motion of multiple droplets in multi-channel systems, using just one light source. Besides static droplets, this approach can also be applied for the directional control of moving droplets in multi-channel systems. As a proof-of-concept, such an approach has been utilized for efficient multiplexed reactions for chemical sensing or microreactor applications. This work offers an alternative approach for the manipulation of droplet movement in applications that involve the control of droplet motion.
离散液滴传输在广泛的应用中引起了极大的关注。然而，控制液滴传输中的运动方向是一个长期存在的挑战。在这项工作中，展示了一种简单而有效的方法，可在具有预定义通道的纳米结构表面上实现对液滴运动的方向控制。光被用作外部刺激，以诱导基底的不均匀热膨胀，这导致纳米结构通道倾斜，从而使液滴沿着通道移动。由于光的易于操控，包括光的位置和功率密度，本研究仅使用一个光源就展示了静态水滴可控地进入目标通道以及在多通道系统中同时控制多个液滴的运动。除了静态液滴，这种方法还可应用于多通道系统中移动液滴的方向控制。作为概念验证，这种方法已被用于化学传感或微反应器应用的高效多重反应。这项工作为涉及液滴运动控制的应用中的液滴运动操纵提供了一种替代方法。
