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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.

Aesthetically appealing photovoltaic (PV) panels with colorful layers are used in numerous applications involving color matching with the surroundings. To develop a colored film for a PV system, appropriate optical properties such as high transparency and low angle sensitivity are necessary because the colored layers can reduce the efficiency of the PV system by causing variations in the transmittance and angle of incidence. Herein, we propose a facile fabrication method for bioinspired three-dimensional (3D) photonic crystal (PC) films that exhibit broad angle-insensitive transmission and reflection, for application in colorful PV. This structure, patterned on a sequentially stacked 11-layer film of SiO