The ability to control the dispersion, aggregation, and assembly of colloidal systems is important for a number of applications, for instance, Pickering emulsions, drug and gene delivery, control of fluid rheology, and the formation of colloidal crystal arrays. We generated a responsive colloidal system based on polymer-brush-grafted silica nanoparticles and demonstrated that such a colloidal s...

A soft glassy colloidal array that was prepared from polymer-grafted silica particles and an ionic liquid showed homogeneous, non-brilliant, angle-independent structural colours.

We describe the synthesis and characterization of stable suspensions of monodisperse fluorescently labeled silica dumbbell particles. Pure dispersions of silica dumbbells with center-to-center lengths from 174 nm to 2.3 microm were produced with a variety of aspect ratios. Individual particles in concentrated dispersions of these particles could be imaged with confocal microscopy. These particl...

Dispersions of hydrophilic fumed silica are investigated in a range of polar organic media. The silica forms stable, low-viscosity sols exhibiting shear thickening behavior in a host of liquids, including ethylene glycol and its oligomers and short-chain alcohols, such as n-propanol. In contrast, the silica flocculates into colloidal gels in other liquids, such as glycols with methyl end-caps a...

In this paper, we report our recent work on preparing two-dimensional patterned microstructure arrays using three-dimensional colloidal crystals as templates, namely, colloidal crystal-assisted lithography. Two alternative processes are described and involved in colloidal crystal-assisted lithography. One is based upon imprinting the polymer films with three-dimensional silica colloidal crystal...

This communication describes a method to fabricate multilayer colloidal crystals formed by the layer-by-layer deposition of silica beads on a glass substrate. Each layer of the crystal consists of a three-dimensionally ordered array of close-packed colloids. These multilayer samples are amenable to templating methods for tuning the dielectric contrast of the material. The resulting photonic cry...

G roundwaters in areas such as Texas, New Mexico, Arizona, California, parts of southern Europe, the Pacific Rim, and Latin America contain high silica concentrations (50 to 100 ppm, as colloidal silica [SiO 2 ]). These levels arise from dissolution of various silicate-containing minerals into the groundwater. Silica precipitation and deposition occur mostly in evaporative cooling systems, wher...

About ten years ago Ryoo and co-workers [1,2] reported the hard-templating (HT) synthesis of ordered mesoporous carbons (OMCs) by using ordered mesoporous silicas (OMSs) as hard templates. Five years afterward the soft-templating (ST) synthesis of OMCs has been discovered [3-6]. Significant progress has been made in both hardand soft-templating synthesis of OMCs [7-10]. Major advances in the sy...