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arXiv · 1203.4361

Building micro-soccer-balls with evaporating colloidal fakir drops

Alvaro G. Marin·Arturo Susarrey-Arce·Hanneke Gelderblom·Arie van Houselt·Leon Lefferts·Han Gardeniers·Detlef Lohse·Jacco Snoeijer
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Abstract

Evaporation-driven particle self-assembly can be used to generate three-dimensional microstructures. We present a new method to create these colloidal microstructures, in which we can control the amount of particles and their packing fraction. To this end, we evaporate colloidal dispersion droplets on a special type of superhydrophobic micro-structured surface, on which the droplet re- mains in Cassie-Baxter state during the entire evaporative process. The remainders of the droplet consist of a massive spherical cluster of the microspheres, with diameters ranging from a few tens up to several hundreds of microns. We present scaling arguments to show how the final particle packing fraction of these balls depends on the dynamics of the droplet evaporation.

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Alvaro G. Marin, Arturo Susarrey-Arce, Hanneke Gelderblom, Arie van Houselt, Leon Lefferts, Han Gardeniers, Detlef Lohse, Jacco Snoeijer. 2012-03-20. Building micro-soccer-balls with evaporating colloidal fakir drops. https://doi.org/10.1073/pnas.1209553109

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