Cho Donghwi, Chen Haomin, Shin Jonghwa, Jeon Seokwoo
Department of Materials Science and Engineering, KAIST Institute for Nanocentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Querrey Simpson Institute for Bioelectronics, Northwestern University, Evanston, IL 60208, USA.
Nanophotonics. 2021 Dec 17;11(11):2737-2762. doi: 10.1515/nanoph-2021-0642. eCollection 2022 Jun.
Smart chromatic materials with optical transmittances that can be modified by light scattering upon external stimuli are attracting extensive interest because of their appealing applications in smart windows, privacy protection, electronic displays, etc. However, the development of these scatterers, which are mostly activated by electric fields, is hindered by their intrinsic energy consumption, slow responses, and poor stability. Recently, mechanoresponsive scatterers based on a strain-driven reconfiguration of the surface or internal structure have emerged, featuring fast responses and a simple composition/fabrication. Because there is no energy consumption to maintain the transparency/opacity, this novel scheme for scatterers holds great promise to break the existing bottleneck. This article presents recent advances in the development of mechanoresponsive scatterers and compares different structural design strategies. The scatterers are categorized into 2D, 3D, and other types according to the dimensions of their functioning structures. The fabrication methods, mechanisms, and relationships between the structural parameters and optical modulating performances are discussed for each category. Next, the potential applications of these scatterers are outlined. Finally, the advantages and disadvantages of the mainstream 2D and 3D categories are summarized, followed by a perspective on future research directions.
智能变色材料具有可通过外部刺激下的光散射来改变光学透过率的特性，因其在智能窗户、隐私保护、电子显示屏等方面的诱人应用而备受关注。然而，这些大多由电场激活的散射体的发展受到其固有能耗、响应缓慢和稳定性差的阻碍。最近，基于表面或内部结构应变驱动重构的机械响应散射体应运而生，具有响应快、组成/制造简单的特点。由于无需消耗能量来维持透明度/不透明度，这种新型散射体方案有望突破现有瓶颈。本文介绍了机械响应散射体发展方面的最新进展，并比较了不同的结构设计策略。根据其功能结构的维度，散射体分为二维、三维和其他类型。针对每一类，讨论了其制造方法、机理以及结构参数与光学调制性能之间的关系。接下来，概述了这些散射体的潜在应用。最后，总结了主流二维和三维类别散射体的优缺点，并展望了未来的研究方向。
