Key Laboratory of Carbon Fibers and Functional Polymers, Ministry of Education; College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, OH, 44242, USA.
Adv Mater. 2019 Mar;31(10):e1807751. doi: 10.1002/adma.201807751. Epub 2019 Jan 11.
Functional soft materials exhibiting distinct functionalities in response to a specific stimulus are highly desirable towards the fabrication of advanced devices with superior dynamic performances. Herein, two novel light-driven chiral fluorescent molecular switches have been designed and synthesized that are able to exhibit unprecedented reversible Z/E photoisomerization behavior along with tunable fluorescence intensity in both isotropic and anisotropic media. Cholesteric liquid crystals fabricated using these new fluorescent molecular switches as chiral dopants exhibit reversible reflection color tuning spanning the visible and infrared region of the spectrum. Transparent display devices have been fabricated using both low chirality and high chirality cholesteric films that operate either exclusively in fluorescent mode or in both fluorescent and reflection mode, respectively. The dual mode display device employing short pitch cholesteric film is able to function on demand under all ambient light conditions including daylight and darkness with fast response and high resolution. Moreover, the proof-of-concept for a "remote-writing board" using cholesteric films containing one of the light-driven chiral fluorescent molecular switches with ease of fabrication and operation is disclosed herein. Such optically rewritable transparent display devices enabled by light-driven chiral fluorescent molecular switches pave a new way for developing novel display technology under different lighting conditions.
具有特定刺激响应功能的软物质在制造具有优越动态性能的先进设备方面非常理想。本文设计并合成了两种新型的光驱动手性荧光分子开关，它们能够在各向同性和各向异性介质中表现出前所未有的可逆 Z/E 光致异构化行为和可调荧光强度。使用这些新型荧光分子开关作为手性掺杂剂制备的胆甾相液晶表现出在可见和红外光谱区域内可逆的反射颜色调谐。使用低手性和高手性胆甾相薄膜分别制造了仅在荧光模式或荧光和反射模式下工作的透明显示器件。采用短螺距胆甾相薄膜的双模式显示器件能够在包括日光和黑暗在内的所有环境光条件下按需工作，具有快速响应和高分辨率。此外，本文还披露了一种使用含有其中一种光驱动手性荧光分子开关的胆甾相薄膜的“遥控书写板”的概念验证，该书写板易于制造和操作。这种由光驱动手性荧光分子开关实现的光可重写透明显示器件为在不同照明条件下开发新型显示技术开辟了新途径。
