Self-assembly of catalytically active colloidal molecules: Tailoring activity through surface chemistry

TL;DR

This paper explores how surface chemistry controls the self-assembly and activity of catalytically active colloidal molecules, revealing how symmetry and surface modifications influence their motion and behavior.

Contribution

It demonstrates the formation of self-assembled colloidal molecules with tunable activity through surface chemistry modifications, highlighting non-equilibrium action-reaction symmetry breaking.

Findings

Colloidal molecules can be inert or active depending on symmetry.

Surface chemistry adjustments alter the activity and motion of colloidal assemblies.

The system exhibits action-reaction symmetry breaking analogous to ionic systems.

Abstract

A heterogeneous and dilute suspension of catalytically active colloids is studied as a non-equilibrium analogue of ionic systems, which has the remarkable feature of action-reaction symmetry breaking. Symmetrically coated colloids are found to join up to form self-assembled molecules that could be inert or have spontaneous activity in the form of net translational velocity and spin depending on their symmetry properties and their constituents. The type of activity can be adjusted by changing the surface chemistry and ambient variables that control the surface reactions and the phoretic drift.