Photonic Crystals with an Eye Pattern Similar to Peacock Tail Feathers

Fabrication of Structural-Coloured Carbon Fabrics by Thermal Assisted Gravity Sedimentation Method

Structural-coloured poly(styrene-methyl methacrylate-acrylic acid) (Poly(St-MMA-AA)) deposited carbon fabrics (Poly(St-MMA-AA)/PCFs) with fascinating colours (salmon, chartreuse, springgreen, skyblue, mediumpurple) changing with the (Poly(St-MMA-AA) nanoparticle sizes can be facilely fabricated by the thermal-assisted gravity sedimentation method that facilitates the self-assembly of Poly(St-MMA-AA) colloidal nanoparticles to generate photonic crystals. The particle sizes of Poly(St-MMA-AA) copolymer with core/shell structure varying from 308.3 nm to 213.1 nm were controlled by adjusting the amount of emulsifier during emulsion polymerisation. The presence of the intrinsic chemical information of Poly(St-MMA-AA) copolymer has been ascertained by Raman and Fourier Transform Infrared (FT-IR) Spectroscopy analysis. Colour variation of the as-prepared structural-coloured carbon fabrics (Poly(St-MMA-AA)/PCFs) before and after dipping treatment were captured while using an optical microscope. The structural colours of Poly(St-MMA-AA)/PCFs were assessed by calculating the diffraction bandgap according to Bragg's and Snell's laws. The Poly(St-MMA-AA) photonic crystal films altered the electrical properties of carbon fabrics with the resistivity growing by five orders of magnitude. The differential electrical resistivity between Poly(St-MMA-AA)/PCFs and wet Poly(St-MMA-AA)/PCFs combined with the corresponding tunable colours can be potentially applied in several promising areas, such as smart displays, especially signal warning displays for traffic safety.

A simple technique for the fabrication of P(St-BA-AA) colloidal crystal microdots on ink-jet paper

The generation of three-dimensional superb packages of compact hexagonal periodic assembly with multifaceted layers was demonstrated using Poly (styrene-butylcrylate-acrylic acid) on glass substrates. The synthesized P(St-BA-AA) microspheres were used to formulate a fast drying UV curable terpolymer microspheres printing ink for the generation of colloidal crystal microdots on ink-jet paper with remarkable colours. The terpolymer microspheres and their formulated terpolymer ink undergo self-assembly to form blue monochromatic and viewing angle dependent tunable colours, thus affirming the photonic nature of the generated colloidal crystal films. Unlike other printing techniques which usually make use of specialized tools, this study generated a well ordered coloured tunable assembly of spherical shaped core-shell colloidal crystal microdots on the surface of an inkjet-paper by manually writing the as-synthesized P(St-BA-AA) UV curable printing ink microdots on it. The TEM analysis showed core and shell sizes of 198/50nm and 176/30nm for P(St-BA-AA)1 and P(St- BA-AA)2 respectively. Whenever the prepared terpolymer microspheres are used within the heating and transition temperatures of 383 °C and 110 °C, their thermal stability is retained. This simple technique of generating crystals microdots on inkjet paper may find use in optical devices, security applications and other colour coating applications.

Nanosphere Lithography for Structuring Polycrystalline Diamond Films

This paper deals with the structuring of polycrystalline diamond thin films using the technique of nanosphere lithography. The presented multistep approaches relied on a spin-coated self-assembled monolayer of polystyrene spheres, which served as a lithographic mask for the further custom nanofabrication steps. Various arrays of diamond nanostructures—close-packed and non-close-packed monolayers over substrates with various levels of surface roughness, noble metal films over nanosphere arrays, ordered arrays of holes, and unordered pores—were created using reactive ion etching, chemical vapour deposition, metallization, and/or lift-off processes. The size and shape of the lithographic mask was altered using oxygen plasma etching. The periodicity of the final structure was defined by the initial diameter of the spheres. The surface morphology of the samples was characterized using scanning electron microscopy. The advantages and limitations of the fabrication technique are discussed. Finally, the potential applications (e.g., photonics, plasmonics) of the obtained nanostructures are reviewed.

Biomimetic superwettable materials with structural colours

This review aims at offering a comprehension elaboration of the mechanism, recent biomimetic research and applications of biomimetic superwettable materials with structural colours. Futhermore, this review will provide significant insight into the design, fabrication and application of biomimetic superwettable materials with structural colours.