Collective Nucleation Dynamics in Two-dimensional Emulsions with Hexagonal Packing

TL;DR

This study uncovers a collective nucleation mechanism in hexagonally packed droplet monolayers, where solidified droplets catalyze neighboring droplet crystallization, emphasizing the importance of collective effects in supercooled emulsions.

Contribution

It introduces a novel collective nucleation mechanism in two-dimensional emulsions, highlighting the influence of droplet contacts and challenging classical nucleation theory.

Findings

Solidified droplets catalyze neighbor nucleation

Cluster size distribution is independent of emulsion properties

Collective effects are significant in supercooled emulsions

Abstract

We report a new mechanism for nucleation in a monolayer of hexagonally packed monodisperse droplet arrays. Upon cooling, we observe solidified droplets to nucleate their supercooled neighbors giving rise to an autocatalytic-like mechanism for accelerated crystallization. This collective mode of nucleation depends on the strength and nature of droplet contacts. Intriguingly, the statistical distribution of the solidified droplet clusters is found to be independent of emulsion characteristics except surfactant. In contrast to classical nucleation theory, our work highlights the need to consider collective effects of nucleation in supercooled concentrated emulsions where droplet crowding is inevitable.