The effect of capillary bridging on the Janus particle stability at the interface of two immiscible liquids

Abstract

Molecular aspects of nanoparticle adsorption to the interface between two immiscible liquids are investigated using molecular dynamics simulations. The effect of particle amphiphilicity on the adsorption and desorption processes is examined by comparing the simulation results of a Janus particle to a plain particle. The force acting on the particle and the free energy of the system as functions of the particle distance from the interface are found to show asymmetry even when the Janus particle is moved quasi-statically. This phenomenon is associated with an asymmetric capillary bridging during the adsorption and desorption processes and the formation of a fluid shell surrounding the Janus cap in the desorbed state.