Dynamics and Collapse of Two-Dimensional Colloidal Lattices

Abstract

One interesting aspect of colloidal particles is the formation of colloidal crystals at the 2D and 3D levels. Here we report the dynamics and collapse of colloidal lattices at liquid-liquid interfaces using Pickering emulsions as an experimental template. The colloidal particles oscillate around their equilibrium positions. The short-time diffusion constant (<10 s) of single particles increases with increasing lattice spacing; the oil-phase viscosity has an effect on diffusion only at large interparticle distances. Strikingly, we observe that the equilibrium structure can be disturbed when increasing the output laser intensity in a confocal laser scanning microscope, which leads to the collapse of colloidal lattices in the presence of small laser powers.

Polymer-assisted self-assembly of gold nanoparticle monolayers and their dynamical switching

“…It does however give some indication of their topology (as we discuss below, optical spectra are needed to estimate the particle separation at the LLI). Monolayer organization at the LLI is favored with the NPs tightly and vertically confined by the stabilization of the interface (the sharp interface potential well prevents bilayers) and laterally balanced by electrostatic, capillary and van der Waals forces 34 which work in complex interplay with the steric repulsion (Fig. 1e).…”

Synthesis of polystyrene–silica composite particles via one-step nanoparticle-stabilized emulsion polymerization

“…In the latter case, the initiator molecules or residues adsorb onto the silica nanoparticle surfaces after initiation [22] thus the silica nanoparticles function as the surface-active initiator residue in that polymerization. This is our first attempt of applying the concept of solid-stabilized emulsions in polymerization, after studying the fundamentals of solid-stabilized emulsions [40][41][42], utilizing them as templates to investigate the dynamics of particles [43][44][45], and developing microrheology at liquid-liquid interfaces [46,47]. Such application may open new avenues of synthesizing advanced materials utilizing the concept of solid-stabilized emulsions.…”

The Structure and Dynamics of Microparticles at Pickering Emulsion Interfaces

“…to a bulk concentration of 0.03%, we are able to assemble colloidal lattices with long-range ordering (Figure 1(b)). The colloidal particles form a nearly ordered array and oscillate around their equilibrium positions, owing to a combination of the underlying crystalline constraint and thermal fluctuation (Lipowsky et al ., 2005;Tarimala et al ., 2006). The lattices are thermodynamically stable and do not change over hours of aging.…”