Colloidal particles may be considered as building blocks for materials, just like atoms are the
bricks of molecules, macromolecules, and crystals. Periodic arrays of colloids (colloidal …

This article presents an overview of current research activities that center on monodispersed
colloidal spheres whose diameter falls anywhere in the range of 10 nm to 1 μm. It is …

Materials whose dielectric constant varies spatially with submicrometer periodicity exhibit
diffractive optical properties which are potentially valuable in a number of existing and …

Colloidal photonic crystals and materials derived from colloidal crystals can exhibit distinct
structural colors that result from incomplete photonic band gaps. Through rational materials …

Three-dimensional crystals of air spheres in titania (TiO2) with radii between 120 and 1000
nanometers were made by filling the voids in artificial opals by precipitation from a liquid …

Colloidal crystals are three-dimensional periodic structures formed from small particles
suspended in solution. They have important technological uses as optical filters1–3 …

Responsive photonic structures can respond to external stimuli by transmitting optical
signals. Because of their important technological applications such as color signage and …

Colloidal crystal-templating methods have been used to prepare inverse opal photonic
crystals of silica, mercaptopropyl-functionalized silica, titania, and zirconia. Ordered arrays of …

We present a detailed study of photonic band structure in certain self-organizing systems
that self-assemble into large-scale photonic crystals with photonic band gaps (PBGs) or …

Fluorescent labeling based on silica nanoparticles facilitates unique applications in
bioanalysis and bioseparation. Dye-doped silica nanoparticles have significant advantages …