Rotational diffusion of partially wetted colloids at fluid interfaces

Colloids at interfaces: Pinned down.

In 1903 Walter Ramsden found that an air bubble placed in a liquid suspension of microscopic particles “can be seen to pick up the particles ... and to retain them obstinately ...”1 Ramsden had discovered the strong affinity of colloidal particles to fluid interfaces, an affinity that a century later can be harnessed to make microstructured materials such as Pickering emulsions, colloidosomes a...

Colloids at Liquid-liquid Interfaces

Rotational diffusion of spherical colloids close to a wall.

There is currently no experimental technique available to probe spatially resolved rotational diffusion of nanoparticles in the vicinity of a wall. We present the first experimental study of rotational diffusion of small spherical colloids, using dynamic evanescent wave scattering. A setup is used where the wave vector components parallel and perpendicular to the wall can be varied independentl...

A Linear Diffusion Model of Adsorption Kinetics at Fluid/Fluid Interfaces

The paper presents a new model for kinetically controlled adsorption at the fluid/fluid interface. The main purpose of the presented approach is to relate easy to estimate bulk surfactant concentration with Gibbs surface excess. Two adsorption isotherms are involved in the new model development: Frumkin and Szyszkowski isotherms. Additionally the Johannsen time profile of concentration in the a...

Molecular simulation of translational and rotational diffusion of Janus nanoparticles at liquid interfaces.

We perform molecular dynamics simulations to understand the translational and rotational diffusion of Janus nanoparticles at the interface between two immiscible fluids. Considering spherical particles with different affinity to fluid phases, both their dynamics as well as the fluid structure around them are evaluated as a function of particle size, amphiphilicity, fluid density, and interfacia...