Recent progress in periodic patterning fabricated by self-assembly of colloidal spheres for optical applications

Colloidal crystals are periodically ordered arrays of monodisperse colloidal particles which represent a new class of self-assembled materials showing potential applications in many fields. Two-dimensional graphic nanostructures based on colloidal crystals have inherent periodicity from tens of nanometers to several micrometers, which gives them rich and interesting optical properties. This article presents a comprehensive review about the current research activities on the self-assembly of colloidal spheres which is an effective strategy for fabrication of various hierarchical and ordered nanostructures, with particular attention paid to the unique properties and applications of the colloidal crystal-based nanostructures. Three main aspects are elaborated: a) controllable self-assembly of colloidal crystals; b) the functions of the obtained colloidal spheres acting as the patterned mask for successive construction of numerous nanostructures; c) the novel properties and promising optical applications of the patterned nanostructures in various domains, such as plasmonic-related fields, antireflection, photonic crystals, photo-catalysis and electronic devices. After that, the current challenges and future perspectives in this area are provided. This review aims to inspire more ingenious designs and exciting research for manufacturing nanostructures utilizing colloidal self-assembly.