Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, P. R. China.
School of Materials Science and Engineering, Peking University, Beijing 100871, P. R. China.
Nano Lett. 2023 May 24;23(10):4617-4626. doi: 10.1021/acs.nanolett.3c01118. Epub 2023 May 10.
Light filters are ubiquitous in projection and display techniques, illumination engineering, image sensing, photography, , while those enabling wide-gamut dynamic light color tuning are still lacking. Herein, by combining the electro-heating capability of graphene and unique optical properties (thermochromism and circular dichroism) of small-molecule-weight cholesteric liquid crystal (ChLC), a brand-new thermochromic light modulator is constructed as actively tunable color filter. Transparent graphene/glass hybrid with reasonably high conductivity serves both as a high-performance heater for actuating the thermochromism of temperature-responsive ChLC and as neutral light attenuator for brightness control. Thanks to the temperature- and polarization-dependent spectral properties of the ChLC, widely tunable hue and saturation properties of transmission light color are achieved, respectively. Several intriguing applications, e.g., color-variable smart windows for backlight color tuning and color-variable filters for photography, are also demonstrated. This work hereby provides new paradigms for promoting the applications of graphene/ChLC-based light modulators in next-generation light-management-related scenarios.
滤光片在投影和显示技术、照明工程、图像感应、摄影等领域无处不在，而能够实现宽色域动态调光的滤光片仍然缺乏。在此，通过结合石墨烯的电热性能和小分子量胆甾相液晶（ChLC）的独特光学特性（热致变色和圆二色性），构建了一种全新的热致变色光调制器，用作主动可调彩色滤光片。具有合理高导电性的透明石墨烯/玻璃杂化材料既可用作温度响应 ChLC 热致变色的高性能加热器，又可用作亮度控制的中性光衰减器。由于 ChLC 的光谱性质随温度和偏振而变化，因此可以实现传输光颜色的色调和饱和度的广泛可调谐。还展示了一些有趣的应用，例如用于背光颜色调谐的可变颜色智能窗户和用于摄影的可变颜色滤光片。这项工作为促进基于石墨烯/ChLC 的光调制器在下一代与光管理相关的场景中的应用提供了新范例。
