Fabrication of polyhedral particles from spherical colloids and their self-assembly into rotator phases

TL;DR

This paper presents a novel method to transform spherical colloids into polyhedral particles with flat facets, enabling the self-assembly into rotator phases, thus expanding the toolkit for designing advanced materials.

Contribution

The study introduces a simple fabrication technique to produce polygonal colloidal particles from spherical ones, facilitating new self-assembly pathways.

Findings

Successful fabrication of polyhedral particles from spherical colloids.

Formation of 3D rotator phases with these particles.

High yield of polygonal particles suitable for self-assembly.

Abstract

Particle shape is a critical parameter that plays an important role in self-assembly, for example, in designing targeted complex structures with desired properties. In the last decades an unprecedented range of monodisperse nanoparticle systems with control over the shape of the particles have become available. In contrast, the choice of micron-sized colloidal building blocks of particles with flat facets, i.e., particles with polygonal shapes, is significantly more limited. This can be attributed to the fact that, contrary to nanoparticles, the larger colloids are significantly harder to synthesize as single crystals. Herein, we demonstrate that the simplest building block, such as the micron-sized polymeric spherical colloidal particle, is already enough to fabricate particles with regularly placed flat facets, including completely polygonal shapes with sharp edges. As an illustration that the yields are high enough for further self-assembly studies we demonstrate the formation of 3D rotator phases of fluorescently labelled, micron-sized and charged rhombic dodecahedron particles. Our method for fabricating polyhedral particles opens a new avenue for designing new materials.