Qiao Shuo, Li Deyu, Yang Lin
Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing 100871, People's Republic of China.
Department of Mechanical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States.
Nano Lett. 2023 Oct 11;23(19):8860-8867. doi: 10.1021/acs.nanolett.3c01795. Epub 2023 Sep 21.
Tailoring heat flow in solids has profound implications for the innovation of functional thermal devices. However, the current methods face technological challenges related to system complexity, material stability, and operating temperature. In this study, we demonstrated efficient heat flow modulation in a single material without a phase transition, using a simple and entirely material-independent strategy, kinked nanostructure patterning, at near-ambient temperature. By carefully controlling the kink arm length and kink angle of the Si nanoribbons, we achieved a thermal conductivity modulation of up to ∼20%. Our theoretical modeling showed that this modulation results from the competing roles of phonon backscattering and open view channels on heat transport. We also build a regime map based on the existence of an open view channel and provide concrete design guidelines for thermal conductivity modulation considering the kink angle and arm length. This study opens up new opportunities for efficient heat flow manipulation through nanostructure patterning.
在固体中定制热流对功能性热器件的创新具有深远意义。然而，当前的方法面临着与系统复杂性、材料稳定性和工作温度相关的技术挑战。在本研究中，我们展示了在接近环境温度下，使用一种简单且完全与材料无关的策略——扭结纳米结构图案化，在无相变的单一材料中实现高效的热流调制。通过仔细控制硅纳米带的扭结臂长度和扭结角度，我们实现了高达约20%的热导率调制。我们的理论模型表明，这种调制源于声子背散射和开放视图通道在热传输中的竞争作用。我们还基于开放视图通道的存在构建了一个状态图，并提供了考虑扭结角度和臂长度的热导率调制的具体设计指南。这项研究为通过纳米结构图案化进行高效热流操纵开辟了新的机会。
