Remotely powered self-propelling particles and micropumps based on miniature diodes
Remotely powered self-propelling particles and micropumps based on miniature diodes
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DOI：
10.1038/nmat1843
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发表时间：
2007-03-01
期刊：
影响因子：
41.2
通讯作者：
Velev, Orlin D.
中科院分区：
文献类型：
--
作者：
Chang, Suk Tai;Paunov, Vesselin N.;Velev, Orlin D.
能够在流体中自动推进的微型传感器和微型机器可能会给技术的许多方面带来革命性的变化。推动这类装置并为其提供能量的原理鲜为人知。在这里，我们展示了各种类型的微型半导体二极管漂浮在水中时，在外部交变电场的驱动下，起到了自推进粒子的作用。毫米大小的二极管整流电极之间感应的电压。由此产生的颗粒局域电渗流将它们推向阴极或阳极的方向，这取决于它们的表面电荷。这些基本的自动推进装置可以发光或对光做出反应，并可以由内部逻辑控制。嵌入在微流体通道壁上的二极管提供由全局外场供电的局部分布的泵浦或混合功能。交流电机的联合应用。和华盛顿特区。这种装置中的电场可以使颗粒和液体的速度解耦，并可用于芯片上的分离。
Microsensors and micromachines that are capable of self-propulsion through fluids could revolutionize many aspects of technology. Few principles to propel such devices and supply them with energy are known. Here, we show that various types of miniature semiconductor diodes floating in water act as self-propelling particles when powered by an external alternating electric field. The millimetre-sized diodes rectify the voltage induced between their electrodes. The resulting particle-localized electro-osmotic flow propels them in the direction of either the cathode or the anode, depending on their surface charge. These rudimentary self-propelling devices can emit light or respond to light and could be controlled by internal logic. Diodes embedded in the walls of micro fluidic channels provide locally distributed pumping or mixing functions powered by a global external field. The combined application of a.c. and d.c. fields in such devices allows decoupling of the velocity of the particles and the liquid and could be used for on-chip separations.