This work explored a facile way to fabricate superhydrophobic and antireflective polymer surfaces using Canna indica flower petals. A simple, inexpensive two-step soft-lithography technique was employed to replicate the surface structures of C. indica flower petals onto two different polymer surfaces namely, polydimethylsiloxane (PDMS) — a hydrophobic polymer and resorcinol–formaldehyde (RF) xerogel — a hydrophilic polymer. First, a negative replica was prepared in PDMS using the flower petal as a template. Second, the negative PDMS replica was later used as a stamp to prepare a positive replica in both PDMS and RF xerogel. These replicated structured surfaces greatly influenced the wettability properties. The contact angle of the replicated PDMS surfaces increased to the nearly superhydrophobic values of 145° (negative PDMS replica) and 144° (positive PDMS replica) compared with that of the plain surface, which is 101°. Interestingly, the contact angle of the replicated RF surface significantly increased to 151° (superhydrophobic) compared with that of the planar RF surface, which is hydrophilic (68°). Furthermore, the replicated polymer surfaces exhibited not only excellent superhydrophobic properties but also antireflective properties. These multifunctional surfaces with superhydrophobicity as well as an omnidirectional antireflective property may find a wide range of applications, such as solar energy harvesting, optical displays and marine applications.

中文翻译：

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模仿花瓣以制造自清洁和抗反射聚合物表面

这项工作探索了一种使用Canna indica花瓣制造超疏水和抗反射聚合物表面的简便方法。一种简单，便宜的两步软光刻技术被用来复制印度。草的表面结构。花瓣撒在两个不同的聚合物表面上，即聚二甲基硅氧烷（PDMS）（一种疏水性聚合物）和间苯二酚-甲醛（RF）干凝胶（一种亲水性聚合物）。首先，使用花瓣作为模板，在PDMS中制备阴性复制品。其次，阴性PDMS副本随后被用作印章，以在PDMS和RF干凝胶中制备阳性副本。这些复制的结构化表面极大地影响了润湿性。与平整表面的101°相比，复制的PDMS表面的接触角增加到145°（负PDMS复制）和144°（正PDMS复制）的几乎超疏水值。有趣的是，与平面RF表面相比，复制的RF表面的接触角显着增加到151°（超疏水），是亲水的（68°）。此外，复制的聚合物表面不仅表现出优异的超疏水性能，而且表现出抗反射性能。这些具有超疏水性和全向抗反射特性的多功能表面可能会找到广泛的应用，例如太阳能收集，光学显示器和海洋应用。