'Fuelled' motion: phoretic motility and collective behaviour of active colloids

TL;DR

This review explores the physical mechanisms, experimental fabrication, and collective behaviors of active colloids propelled by phoretic effects, highlighting recent advances in understanding their motion and interactions.

Contribution

It provides a comprehensive tutorial on phoretic motion mechanisms, experimental fabrication methods, and theoretical tools for analyzing collective behaviors of active colloids.

Findings

Phoretic effects enable self-propulsion of colloids through local field gradients.

Experimental techniques have successfully fabricated various active particles based on phoretic principles.

Collective behaviors of active colloids include complex assembly and interaction patterns.

Abstract

Designing microscopic and nanoscopic self-propelled particles and characterising their motion has become a major scientific challenge over the past decades. To this purpose, phoretic effects, namely propulsion mechanisms relying on local field gradients, have been the focus of many theoretical and experimental studies. In this review, we adopt a tutorial approach to present the basic physical mechanisms at stake in phoretic motion, and describe the different experimental works that lead to the fabrication of active particles based on this principle. We also present the collective effects observed in assemblies of interacting active colloids, and the theoretical tools that have been used to describe phoretic and hydrodynamic interactions.