Self-assembly of binary nanoparticle dispersions: from square arrays and stripe phases to colloidal corrals

TL;DR

This study uses Monte Carlo simulations to explore pattern formation in binary colloidal mixtures, revealing diverse structures like square arrays, stripe phases, and colloidal corrals with potential technological applications.

Contribution

It demonstrates the unexpected versatility of a simple isotropic core-corona model to produce various technologically relevant nanopatterns.

Findings

Formation of regular square lattice patterns

Emergence of stripe phases in colloidal mixtures

Observation of colloidal corrals as surface templates

Abstract

The generation of nanoscale square and stripe patterns is of major technological importance since they are compatible with industry-standard electronic circuitry. Recently, a blend of diblock copolymer interacting via hydrogen-bonding was shown to self-assemble in square arrays. Motivated by those experiments we study, using Monte Carlo simulations, the pattern formation in a two-dimensional binary mixture of colloidal particles interacting via isotropic core-corona potentials. We find a rich variety of patterns that can be grouped mainly in aggregates that self-assemble in regular square lattices or in alternate strips. Other morphologies observed include colloidal corrals that are potentially useful as surface templating agents. This work shows the unexpected versatility of this simple model to produce a variety of patterns with high technological potential.