Ryabchun Alexander, Lancia Federico, Katsonis Nathalie
Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
ACS Appl Mater Interfaces. 2021 Jan 27;13(3):4777-4784. doi: 10.1021/acsami.0c20006. Epub 2021 Jan 11.
Nano- and micro-actuating systems are promising for application in microfluidics, haptics, tunable optics, and soft robotics. Surfaces capable to change their topography at the nano- and microscale on demand would allow control over wettability, friction, and surface-driven particle motility. Here, we show that light-responsive cholesteric liquid crystal (LC) networks undergo a waving motion of their surface topography upon irradiation with light. These dynamic surfaces are fabricated with a maskless one-step procedure, relying on the liquid crystal alignment in periodic structures upon application of a weak electric field. The geometrical features of the surfaces are controlled by tuning the pitch of the liquid crystal. Pitch control by confinement allows engineering one-dimensional (1D) and two-dimensional (2D) structures that wave upon light exposure. This work demonstrates the potential that self-organizing systems might have for engineering dynamic materials, and harnessing the functionality of molecules to form dynamic surfaces, with nanoscale precision over their waving motion.
纳米和微驱动系统在微流体、触觉、可调光学和软体机器人领域具有广阔的应用前景。能够按需在纳米和微米尺度上改变其形貌的表面将实现对润湿性、摩擦力和表面驱动粒子运动的控制。在此，我们展示了光响应胆甾型液晶（LC）网络在光照下其表面形貌会发生波动运动。这些动态表面是通过无掩模一步法制造的，该方法依赖于在施加弱电场时液晶在周期性结构中的取向。通过调整液晶的螺距来控制表面的几何特征。通过限制进行螺距控制可设计出在光照下会波动的一维（1D）和二维（2D）结构。这项工作展示了自组织系统在工程动态材料以及利用分子功能形成动态表面方面的潜力，并且能够在其波动运动上实现纳米级精度控制。
