Controllable Fabrication Of Micro-shaped Photonic Crystal Assemblies

Enormous research efforts have been made to self-assemble monodisperse colloidal spheres into special microscopic shapes(e. g. super-beads, super-balls or doughnuts), due to their widespread applications in sensors, displays, separation processes, catalysis and etc. But realization of photonic crystal(PC) assemblies with both facile micro-shape control and non-iridescent property is still a tough task. Herein, we demonstrate the controllable fabrication of non-iridescent micro-shaped PC assemblies by evaporation induced self-assembly inside aqueous colloidal dispersion droplet templates on superhydrophobic(SHB)substrates.The main contents are as follows:1.The controllable fabrication of non-iridescent micro-shaped PC assemblies. The micro-shapes of the PC assemblies could be tuned from micro-beads, micro-wells to micro-ellipsoids by manipulating the dynamic behaviors of the three-phase contact line of the colloidal droplets during evaporating process. Structure characterization shows that the PC assemblies are crack-free, consisting of ordered periodic arrangement of colloidal spheres in the surface layers and amorphous inner layers.2.The controllable fabrication of micro-shaped PC assemblies with enhanced non-iridescent structural colors and superparamagnetic property. The incorporation of black Fe3O4 nanoparticles into the PC assembly lattice is demonstrated to be able to endow the PC assemblies with enhanced non-iridescent structural colors with wide-viewing angles and superparamagnetic property. The crack-free non-iridescent PC assemblies with controlled micro-shapes have promising applications in fields of nontoxic non-bleaching pigments, energy-efficient full-color display pixels, and their facile fabrication procedure may provide guidance for creating new types of substructured colloidal particles.3.The controllable fabrication of micro-shaped PC assemblies on clover leaves. To achieve fast fabrication of micro-shaped PC assemblies and prove the universality ofas-developed approach for fabrication of special micro-shaped PC super-assemblies, we chose clover leaves as the other SHB substrate to test our method. Firstly, A colloidal droplet spraying method for fast production of PC super-assemblies with sizes of 30 μm to 300 μm was developed. Then, micro-shaped PC super-assemblies that was fabricated on two kinds of Superhydrophobic substrates was compared and the results prove the universality of as-developed approach for fabrication of micro-shaped PC super-assemblies.