Chen Xi, Chen Xiaowen, Elsayed Mohamed, Edwards Harrison, Liu Jiayu, Peng Yixin, Zhang H P, Zhang Shuailong, Wang Wei, Wheeler Aaron R
Sauvage Laboratory for Smart Materials, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
Institute of Biomedical Engineering, University of Toronto, Toronto M5S 3E1, Canada.
ACS Nano. 2023 Mar 28;17(6):5894-5904. doi: 10.1021/acsnano.2c12811. Epub 2023 Mar 13.
Steering micromotors is important for using them in practical applications and as model systems for active matter. This functionality often requires magnetic materials in the micromotor, taxis behavior of the micromotor, or the use of specifically designed physical boundaries. Here, we develop an optoelectronic strategy that steers micromotors with programmable light patterns. In this strategy, light illumination turns hydrogenated amorphous silicon conductive, generating local electric field maxima at the edge of the light pattern that attracts micromotors via positive dielectrophoresis. As an example, metallo-dielectric Janus microspheres that self-propelled under alternating current electric fields were steered by static light patterns along customized paths and through complex microstructures. Their long-term directionality was also rectified by ratchet-shaped light patterns. Furthermore, dynamic light patterns that varied in space and time enabled more advanced motion controls such as multiple motion modes, parallel control of multiple micromotors, and the collection and transport of motor swarms. This optoelectronic steering strategy is highly versatile and compatible with a variety of micromotors, and thus it possesses the potential for their programmable control in complex environments.
对于将微电机应用于实际以及作为活性物质的模型系统而言，微电机的操控至关重要。此功能通常需要微电机中含有磁性材料、具备微电机的趋性，或者使用专门设计的物理边界。在此，我们开发了一种光电策略，可通过可编程光图案来操控微电机。在该策略中，光照使氢化非晶硅导电，在光图案边缘产生局部电场最大值，通过正介电泳吸引微电机。例如，在交流电场下自行推进的金属 - 电介质双面微球，可由静态光图案沿着定制路径并穿过复杂微结构进行操控。它们的长期方向性也可通过棘轮形状的光图案进行矫正。此外，在空间和时间上变化的动态光图案能够实现更高级的运动控制，如多种运动模式、多个微电机的并行控制以及电机群的收集和运输。这种光电操控策略具有高度通用性，且与多种微电机兼容，因此在复杂环境中对其进行可编程控制具有潜力。
