Equilibrium orientation and adsorption of an ellipsoidal Janus particle at a fluid-fluid interface

TL;DR

This study models and simulates how an ellipsoidal Janus particle orients itself at a fluid interface, revealing the influence of interface deformation and particle properties on equilibrium states.

Contribution

It introduces free energy models and compares them with lattice Boltzmann simulations to understand Janus particle orientation at fluid interfaces.

Findings

Interface deformation affects equilibrium orientation.

Particle aspect ratio and wettability contrast determine final orientation.

Theoretical predictions align with simulation results.

Abstract

We investigate the equilibrium orientation and adsorption process of a single, ellipsoidal Janus particle at a fluid-fluid interface. The particle surface comprises equally sized parts that are hydrophobic or hydrophilic. We present free energy models to predict the equilibrium orientation and compare the theoretical predictions with lattice Boltzmann simulations. We find that the deformation of the fluid interface strongly influences the equilibrium orientation of the Janus ellipsoid. The adsorption process of the Janus ellipsoid can lead to different final orientations determined by the interplay of particle aspect ratio and particle wettablity contrast.