A lattice Boltzmann model for self-diffusiophoretic particles near and at liquid-liquid interfaces

TL;DR

This paper presents a new lattice Boltzmann computational model for simulating self-phoretic particles near liquid-liquid interfaces, capturing complex multiphysics interactions including wettability and solubility effects.

Contribution

The authors develop and validate a versatile multiphase-multicomponent lattice Boltzmann model for active particles at interfaces, incorporating detailed hydrodynamics and physicochemical properties.

Findings

Particle motion can be controlled by tuning mobility, contact angle, and solubility.

The model accurately predicts particle behavior near interfaces.

Simulation results align with theoretical expectations.

Abstract

We introduce a novel mesoscopic computational model based on a multiphase-multicomponent lattice Boltzmann method for the simulation of self-phoretic particles in the presence of liquid-liquid interfaces. Our model features fully resolved solvent hydrodynamics and, thanks to its versatility, it can handle important aspects of the multiphysics of the problem, including particle wettability and differential solubility of the product in the two liquid phases. The method is extensively validated in simple numerical experiments, whose outcome is theoretically predictable, and then applied to the study of the behaviour of active particles next to and trapped at interfaces. We show that their motion can be variously steered by tuning relevant control parameters, such as the phoretic mobilities, the contact angle and the product solubility.