Nature provides various exquisite photonic structures of antireflection. Here, we investigate the color and structure of the inner surface of the shell edge (ISSE) of blue mussel shells, using a fiber optical spectrometer, scanning electron microscope (SEM), and X-ray diffraction (XRD). We demonstrate that the structurally assisted black color of the ISSE is produced by a pyramidal microstructure. Furthermore, we use the two-step biotemplate (TSBT) method to successfully replicate this microstructure. Particularly, we modify this method by using a poly(vinyl alcohol) (PVA) film as the negative replica and an epoxy resin film as the positive replica both fabricated without vacuum treatment. We show that the natural and replicated structures show a reflectivity of ∼4% and of ∼3% in the visible wavelength. Finally, we hope our investigation can provide basic data for the study of the bioinspired antireflective structures, which have a promising application in smart windows and optical devices.

中文翻译：

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蓝贻贝贝壳的自然抗反射微结构和仿生复制。

大自然提供了各种精致的防反射光子结构。在这里，我们使用光纤光谱仪，扫描电子显微镜（SEM）和X射线衍射（XRD）研究蓝贻贝壳的壳边缘（ISSE）内表面的颜色和结构。我们证明了ISSE的结构辅助黑色是由锥体微观结构产生的。此外，我们使用两步生物模板（TSBT）方法来成功复制此微结构。特别是，我们通过使用聚乙烯醇（PVA）膜作为负复制品和环氧树脂膜作为正复制品来修改此方法，两者均未经真空处理。我们表明，自然结构和复制结构在可见光波长下的反射率约为4％，而反射率约为3％。最后，