Abstract
Oil-in-water emulsion droplets spontaneously adopt, below some temperature Td, counterintuitive faceted and complex non-spherical shapes while remaining liquid. This transition is driven by a crystalline monolayer formed at the droplets' surface. Here, we show that ppm-level doping of the droplet's bulk by long-chain alcohols allows tuning Td by >50 °C, implying formation of drastically different interfacial structures. It finds that “magic” alcohol chain lengths maximize Td. This is shown to arise from self-assembly of mixed alcohol:alkane interfacial structures of stacked alkane layers, co-crystallized with hydrogen-bonded alcohol dimers. It accounts for these structures theoretically and resolve them by direct cryogenic transmission electron microscopy (cryoTEM), confirming the proposed structures. The discovered tunability of key properties of commonly-used emulsions by minute concentrations of specific bulk additives should benefit these emulsions' technological applicability.
| Original language | English |
|---|---|
| Number of pages | 8 |
| Journal | Small |
| Early online date | 31 May 2023 |
| DOIs | |
| State | E-pub ahead of print - 31 May 2023 |
Bibliographical note
Funding Information:S.H. and S.R.L. contributed equally to this work. This research was supported by the Israel Science Foundation (grant no. 2205/21). The authors thank the Kahn Foundation for the funding of the equipment. The authors also thank Hiroki Matsubara (Hiroshima University), Luca Giomi, and Ireth Garcia‐Aguilar (Leiden University) for discussions. The authors are grateful to Max Izoh and Ovadia Bezalel for their skillful technical assistance.
Publisher Copyright:
© 2023 The Authors. Small published by Wiley-VCH GmbH.
Keywords
- alcohols
- alkanes
- alkanols
- curved 2D crystals
- emulsion
- faceted droplets
- interfacial freezing