Optical materials with dynamic colors have shown great prospects for applications in display devices, smart windows, and camouflage coatings. Recently, intercalation has been demonstrated to be a powerful strategy for tuning electromagnetic properties of two-dimensional materials ranging from visible to microwave wavelengths, such as the visible color, infrared emission, terahertz radiation, and optical second-harmonic generation. Here, a systematic study of graphene intercalation compound (GIC)-based coloration films is presented. Through lithium (Li), sulfuric acid (H₂SO₄), and ferric chloride (FeCl₃) intercalation, the color of a multilayer graphene (MLG) film transforms from gray to yellow, blue, and dark, respectively. This is attributed to the reconstruction of the band structure of graphene after intercalation, resulting in a significant effect on its optical properties. Furthermore, tunable and reversible color changes of MLG film have been demonstrated by precisely controlling the Li-intercalation process. Our research indicates that intercalation is a versatile strategy for fabricating advanced coloration materials and provides a promising tunable optical surface for the application in sensing, adaptive camouflage, and smart displaying.

中文翻译：

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石墨烯基可调谐着色膜通过插层

具有动态色彩的光学材料在显示设备、智能窗和伪装涂层等方面显示出广阔的应用前景。最近，插层已被证明是一种强大的策略，用于调节从可见光到微波波长范围内的二维材料的电磁特性，例如可见光颜色、红外发射、太赫兹辐射和光学二次谐波产生。在这里，介绍了基于石墨烯插层化合物 (GIC) 的着色膜的系统研究。通过锂 (Li)、硫酸 (H ₂ SO ₄ ) 和氯化铁 (FeCl ₃) 插入，多层石墨烯 (MLG) 膜的颜色分别从灰色变为黄色、蓝色和深色。这归因于嵌入后石墨烯能带结构的重构，对其光学性能产生显着影响。此外，通过精确控制锂嵌入过程，已经证明了 MLG 薄膜的可调和可逆的颜色变化。我们的研究表明，嵌入是制造高级着色材料的通用策略，并为传感、自适应伪装和智能显示中的应用提供了有前景的可调光学表面。