Confinement-induced enhancement of diffusiophoretic forces on self-propellers

TL;DR

This paper investigates how spatial confinement enhances diffusiophoretic forces on self-propelling particles, revealing significant increases especially in two-dimensional environments, with implications for designing active colloids.

Contribution

It demonstrates that confinement notably amplifies diffusiophoretic forces on self-propellers, especially in 2D systems, using a simplified chemical reaction-driven model.

Findings

Force increases with confinement

Enhancement is more pronounced in 2D systems

Confinement can be used to control propulsion strength

Abstract

We study the effect of spatial confinement on the strength of propulsive diffusiophoretic forces acting on a particle that generates density gradients by exploiting the chemical free energy of its environment. Using a recently proposed simple model of a self-propelling device driven by chemical reactions taking place on some parts of its surface, we demonstrate that the force significantly increases in the presence of confining walls. We also show that such effects become even more pronounced in two-dimensional systems.