The research in the Soft Matter & Interfaces Research Group is collaborative and interdisciplinary. The areas span from colloid and interface sciences and engineering, physics of fluids to advanced materials. Current topics include:

  • Formation and properties of micro-/nano- scale bubbles and droplets

  • Chemical reactions of nanodroplets

  • (De-)wetting of liquid on complex surfaces

  • Evaporation in multicomponent systems

  • Dilution-triggered microphase separation

  • Functional surface microstructures for solar harvesting

Featured Research Articles

Review of Modern Physics, Volume 87, Number 3. Surface nanobubbles and nanodroplets
Collective interactions in the nucleation and growth of surface droplets
3D spherical-cap fitting procedure for (truncated) sessile nano- and micro-droplets & -bubbles
Dissolution dynamics of a suspension droplet in a binary solution for controlled nanoparticle assembly
Self-wrapping of an ouzo drop induced by evaporation on a superamphiphobic surface
Mixed mode of dissolving immersed nanodroplets at a solid-water interface
Diffusive interaction of multiple surface nanobubbles: shrinkage, growth, and coarsening
Soft Matter Vol. 14 issue 25. July 2018

Formation of Nanodroplets by Solvent Exchange

The Solvent Exchange, which was inspired by Ouzo - a famous Greek drink, has been recognized as a highly efficient way to form surface nanodroplets and nanobubbles. Compared with other known methods to form nanobubbles and nanodroplets, the solvent exchange is simple and easy to control. This method is based on the oversaturation principle. When a good solvent - a saturated solute A solution (solution A) is replaced by a poor solvent - a saturated solute B solution (solution B), an oversaturation is formed at the interface between solution A and solution B and nanodroplets or nanobubbles are formed in the interface.

More information in the following publications:

Nanodroplet Branch Formation

The video speed is 20 times real time

Detected Nanodroplet Branch Formation

Video of the detected branch structure corresponding to the previous video. The video speed is 100 times real time.

Tracked Colloidal Particles

More information for the videos related to nanodroplet branch formation and tracked colloidal particles go to the publication:

Lu, Z. Y.; Schaarsberg, M. H. K.; Zhu, X. J.; Yeo, L. Y.; Lohse, D.; Zhang, X. H., Universal nanodroplet branches from confining the Ouzo effect. Proceedings of the National Academy of Sciences of the United States of America 2017, 114 (39), 10332-10337.

Flow rate dependence in the Growth of Surface Nanodroplets

5% 1-Octanol, 4x playback, time ~ 10 s; H= 150 um (micrometers)

Growing nanodroplets during solvent exchange

For more information about the videos related to flow rate dependence, go to the following publications:

Collective Effects in Microbubble Growth by Solvent Exchange

Peng, S. H.; Mega, T. L.; Zhang, X. H., Collective Effects in Microbubble Growth by Solvent Exchange. Langmuir 2016, 32 (43), 11265-11272.