Wu Suli, Huang Baoting, Wu Yue, Meng Zhipeng, Zhang Shufen
State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Linggong Road, Dalian 116024, P.R. China.
Nanoscale. 2020 Jun 4;12(21):11460-11467. doi: 10.1039/d0nr00405g.
Management of reflection and transmission two-way structural colors is significant in color displays, projections, and anticounterfeiting. Here, inspired by the Lycurgus Cup, we fabricated photonic crystals with opal and inverse opal structures with controlled thickness, which show reflection and transmission two-way structural colors. In order to balance the reflection and transmission intensities, we first studied the effect of the order layer thickness on the reflection and transmission spectra and found that a thickness of about 5 μm can help the structural colors achieve high saturation in both directions. The photonic crystal film built with 295 nm SiO2 spheres shows bright red and green structural colors in the reflection and transmission directions, respectively. These two-way colors can be projected onto substrates, similar to a transflective color filter. The color displays can be tuned by adjusting the angle between the incident light and the sample. Furthermore, we also patterned the photonic crystal film with two-way structural colors, which shows clear patterns and rich colors in both directions. The photonic crystals assembled on a small wine glass display two-way structural colors similar to those of the Lycurgus Cup. More importantly, a flexible inverse opal photonic crystal film with two-way structural colors was also fabricated, which can be applied in multimode anticounterfeiting. This work will greatly expand the application field of photonic crystals in double sided displays, transflective color filters and anticounterfeiting.
反射和透射双向结构色的管理在彩色显示、投影和防伪方面具有重要意义。在此，受莱库古杯启发，我们制备了具有可控厚度的蛋白石和反蛋白石结构的光子晶体，它们呈现出反射和透射双向结构色。为了平衡反射和透射强度，我们首先研究了有序层厚度对反射和透射光谱的影响，发现约5μm的厚度有助于结构色在两个方向上都实现高饱和度。用295nm二氧化硅球体构建的光子晶体薄膜在反射和透射方向上分别呈现出鲜艳的红色和绿色结构色。这两种双向颜色可以投射到基板上，类似于半透半反滤色器。通过调整入射光与样品之间的角度可以调节彩色显示。此外，我们还用双向结构色对光子晶体薄膜进行了图案化处理，其在两个方向上都呈现出清晰的图案和丰富的颜色。组装在小酒杯上的光子晶体呈现出与莱库古杯相似的双向结构色。更重要的是，还制备了具有双向结构色的柔性反蛋白石光子晶体薄膜，可应用于多模式防伪。这项工作将极大地拓展光子晶体在双面显示、半透半反滤色器和防伪方面的应用领域。
