Inspired by cicada wings, a flexible film with self-cleaning and broadband antireflection properties was fabricated with a rapid, straightforward and cost-effective method. The cicada wing was selected as the original template, and a polymethyl methacrylate (PMMA) negative replica was obtained by evaporation solvent process. The original template was directly peeled off. Subsequently, the polydi-methylsiloxane (PDMS) was spread in the as-prepared PMMA negative replica. After curing and peeling processes, the PDMS positive replica was manufactured successfully. The morphologies and performances of cicada wings were perfectly inherited by the PDMS positive replica. What is more, the excellent optical property of cicada wing was investigated experimentally and theoretically. Compared with flat PDMS film, the average reflectivity of structural PDMS film was reduced from 9% to 3.5% in the wavelength range of 500 nm–900 nm. These excellent antireflection properties of bio-inspired antireflection film can be attributed to the nanostructures which achieve a gradient refractive index between air and the materials, and the mechanism of the antireflection properties was revealed via effective medium theory. Besides, the bio-inspired broadband antireflective film exhibited superhydrophobic property after the surface treatment (a 152.1°water contact angle), and it also displayed satisfactory flexibility. This work provided a universal method to fabricate the exquisite biological structures, realizing the transfer of structure and function. Moreover, the multifunctional antireflection film exhibited the potential value for applications in optical communications, flexible display screens, and anti-dazzle glasses.

中文翻译：

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从蝉翼复制的仿生防反射膜的快速制备

受蝉翼的启发，采用快速，简单且经济高效的方法制造了具有自清洁和宽带减反射特性的柔性薄膜。选择蝉翼作为原始模板，并通过蒸发溶剂工艺获得了聚甲基丙烯酸甲酯（PMMA）负片。直接将原始模板剥离。随后，将聚二甲基硅氧烷（PDMS）分散在已准备好的PMMA底片中。经过固化和剥离过程后，PDMS阳性复制品成功生产。蝉翼的形态和性能被PDMS阳性复制品完美继承。此外，通过实验和理论研究了蝉翼的优异光学性能。与平面PDMS膜相比，在500 nm–900 nm波长范围内，结构PDMS膜的平均反射率从9％降低到3.5％。这些具有生物启发性的减反射膜优异的减反射性能可归因于在空气和材料之间实现梯度折射率的纳米结构，并揭示了减反射性能的机理。通过有效的媒介理论。此外，生物启发的宽带抗反射膜在表面处理后表现出超疏水性（152.1°水接触角），并且还显示出令人满意的柔韧性。这项工作提供了一种通用的方法来制造精致的生物结构，实现结构和功能的转移。此外，多功能减反射膜在光通信，柔性显示屏和防眩眼镜中具有潜在的应用价值。