College of Applied Sciences, Beijing University of Technology, Beijing 100124, P. R. China.
Nanoscale. 2018 Jun 14;10(23):11158-11164. doi: 10.1039/c8nr03622e.
Photo-driven actuators are highly desirable in various smart systems owing to the advantages of wireless control and possible actuation by solar energy. Miniaturization of photo-driven actuators is particularly essential in micro-robotics and micro-/nano-electro-mechanical systems. However, it remains a great challenge to build up nano-scale photo-driven actuators with competitive performance in amplitude, response speed, and lifetime. In this work, we developed photo-driven nanoactuators based on bimorph structures of vanadium dioxides (VO2) and carbon nanocoils (CNCs). Activated by the huge structural phase transition of VO2, the photo-driven VO2/CNC nanoactuators deliver a giant amplitude, a fast response up to 9400 Hz, and a long lifetime more than 10 000 000 actuation cycles. Both experimental and simulation results show that the helical structure of CNCs enables a low photo-driven threshold of VO2/CNC nanoactuators, which provides an effective method to construct photo-driven nanoactuators with low power consumption. Our photo-driven VO2/CNC nanoactuators would find potential applications in nano-scale electrical/optical switches and other smart devices.
光驱动执行器由于其无线控制和可能由太阳能驱动的优点，在各种智能系统中非常理想。在微机器人技术和微/纳机电系统中，光驱动执行器的小型化尤为重要。然而，构建具有竞争性能的纳米级光驱动执行器，在振幅、响应速度和寿命方面仍然是一个巨大的挑战。在这项工作中，我们基于二氧化钒（VO2）和碳纳米线圈（CNC）的双折射结构开发了光驱动纳米执行器。在 VO2 的巨大结构相变的作用下，光驱动的 VO2/CNC 纳米执行器实现了巨大的振幅、高达 9400 Hz 的快速响应和超过 1000 万次驱动循环的长寿命。实验和模拟结果均表明，CNC 的螺旋结构使 VO2/CNC 纳米执行器的光驱动阈值降低，这为构建低功耗光驱动纳米执行器提供了一种有效方法。我们的光驱动 VO2/CNC 纳米执行器将在纳米级电/光开关和其他智能设备中找到潜在的应用。
