Physics of Fluids - Publications

Evaporation-driven colloidal cluster assembly using droplets on superhydrophobic fractal-like structures

Open Access
Soft Matter 17, 506–515 (2021)

Authors

	Carola Seyfert
	Erwin J. W. Berenschot
	Niels R. Tas
	Arturo Susarrey-Arce
	Alvaro Marin

BibTeΧ

@Article{D0SM01346C,
author ="Seyfert, Carola and Berenschot, Erwin J. W. and Tas, Niels R. and Susarrey-Arce, Arturo and Marin, Alvaro",
title  ="Evaporation-driven colloidal cluster assembly using droplets on superhydrophobic fractal-like structures",
journal  ="Soft Matter",
year  ="2020",  
pages  ="-",
publisher  ="The Royal Society of Chemistry",
doi  ="10.1039/D0SM01346C",
url  ="http://dx.doi.org/10.1039/D0SM01346C",
abstract  ="Microparticles can be considered building units for functional systems{,} but their assembly into larger structures typically involves complex methods. In this work{,} we show that a large variety of macro-agglomerate clusters (“supra-particles”) can be obtained{,} by systematically varying the initial particle concentration in an evaporating droplet{,} spanning more than 3 decades. The key is the use of robust superhydrophobic substrates: in this study we make use of a recently discovered kind of patterned surface with fractal-like microstructures which dramatically reduce the contact of the droplet with the solid substrate. Our results show a clear transition from quasi-2D to 3D clusters as a function of the initial particle concentration{,} and a clear transition from unstable to stable 3D spheroids as a function of the evaporation rate. The origin of such shape transitions can respectively be found in the dynamic wetting of the fractal-like structure{,} but also in the enhanced mechanical stability of the particle agglomerate as its particle packing fraction increases."}