Department of Mechanical Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 04107, Korea.
Department of Biomedical Engineering, Sogang University, 35 Baekbeom-ro, Mapo-gu, Seoul 04107, Korea.
Sci Rep. 2017 Mar 21;7:44927. doi: 10.1038/srep44927.
Structure-dependent colour is caused by the interaction of light with photonic crystal structures rather than pigments. The elytra of longhorn beetles Tmesisternus isabellae appear to be iridescent green in a dry state and turn to red when exposed to humidity. Based on the hygroscopic colouration of the longhorn beetle, we have developed centimeter-scale colorimetric opal films using a novel self-assembly method. The micro-channel assisted assembly technique adopts both natural evaporation and rotational forced drying, enhancing the surface binding of silica particles and the packing density by reducing the lattice constant and structural defects. The fabricated large-scale photonic film changes its structural colour from green to red when exposed to water vapour, similarly to the colorimetric feature of the longhorn beetle. The humidity-dependent colour change of the opal film is shown to be reversible and durable over five-hundred cycles of wetting and drying.
结构色是由光与光子晶体结构的相互作用而产生的，而不是由色素产生的。天牛科天牛属 Isabella 的鞘翅在干燥状态下呈现出虹绿色，而在暴露于湿度时会变成红色。基于长角甲虫的吸湿变色特性，我们使用一种新的自组装方法开发了厘米级的比色蛋白石薄膜。微通道辅助组装技术采用自然蒸发和旋转强制干燥，通过减小晶格常数和结构缺陷来增强二氧化硅颗粒的表面结合和堆积密度。所制备的大规模光子薄膜在暴露于水蒸气时会从绿色变为红色，类似于长角甲虫的比色特征。这种蛋白石薄膜的湿度依赖的颜色变化是可逆的，并且在五百次润湿和干燥循环后仍然具有耐用性。
