Iridescent and Glossy Effect on Polymer Surface Using Micro-/Nanohierarchical Structure: Artificial Queen of the Night Tulip Petals

Abstract

Many petals in nature have a hierarchical structure that imparts various optical properties. Among these, the petals of the Queen of the Night tulip exhibit an iridescent and glossy color due to the diffraction and scattering of light. Herein, we report a bioinspired micro-/nanohierarchical structure that mimics Queen of the Night tulip petal surfaces. Using a method that combined soft lithography and UV−ozone treatment, we fabricated nanoscale line patterns with a linewidth of 600 nm on microwrinkles of 15 μm width and 3 μm height. Using optical microscopy in the dark-field mode and monochromatic light diffraction measurements, we found that these hierarchical structures on a poly(dimethylsiloxane) (PDMS) substrate synergistically improved the scattering and diffraction effects, unlike the pristine, nano-, and microstructures. In addition, using a dye-colored PDMS material, we fabricated artificial Queen of the Night petals with iridescent and glossy effects. They show great potential for a range of applications, such as coloring, smart displays, dynamic gratings, and light-control devices.

Flower Inspiration: Broad‐Angle Structural Color through Tunable Hierarchical Wrinkles in Thin Film Multilayers

“…For example, a bio‐inspired structure resembling Queen of the Night tulip petals, formed by wrinkling a film containing a pre‐etched nano‐grating, mimicked the flower's iridescent effect of this flower and the angle broadening of diffraction. [ 31 ] However, none of the previous studies integrate intrinsic multilevel developmental processes, thus limiting their tunability.…”

“…Wrinkling, through the growth of cuticle on bulged epidermal cells, [25] gives rise to the tunability of hierarchical structures that control the broad angle spectrum of structural color in different regions. Recent examples in the literature [26][27][28][29][30][31] provide some of these attributes. For example, a bio-inspired structure resembling Queen of the Night tulip petals, formed by wrinkling a film containing a pre-etched nano-grating, mimicked the flower's iridescent effect of this flower and the angle broadening of diffraction.…”

Wearable Triboelectric Strain-Insensitive Pressure Sensors Based on Hierarchical Superposition Patterns

“…First, the dome array pattern is obtained through the double-casting method of the PDMS. , After that, PDMS is stretched by 80% and then is irradiated with ultraviolet/ozone (UVO). As a result, a wrinkle pattern that is constantly repeated in the horizontal axis direction is generated . We can obtain a novel superposition pattern through the above process.…”

“…As a result, a wrinkle pattern that is constantly repeated in the horizontal axis direction is generated. 29 We can obtain a novel superposition pattern through the above process.…”

Photo‐Polymerization Induced Hierarchical Pattern via Self‐Wrinkling

“…[30][31][32] Based on the classic bilayer system, a series of hierarchical wrinkle patterns have been fabricated by synergy of different external stimulation like stress or light. [33][34][35] However, the wrinkles formed in natural world is always self-organized and spontaneous. Examples of self-wrinkling have been reported based on the homogeneous system wrinkled with abrupt volume or swelling change [36] and gradient system with gradient chemical/physical property (degree of crosslinking, [37] catalyst concentration [38] ).…”