Controlling the buckling instability of drying droplets of suspensions through colloidal interactions

Soft Matter. 2015 May 14;11(18):3660-5. doi: 10.1039/c5sm00283d.

Abstract

The present study focuses on the drying of droplets of colloidal suspensions using the Leidenfrost effect. At the end of drying, grains show different morphologies: cups or spheres depending on the ionic strength or zeta potential of the initial suspension. High ionic strengths and low absolute zeta potential values lead to spherical morphologies. A model based on the calculations of DLVO potentials has been implemented to extract a critical pressure, which provides a quantitative criterion for buckling whatever the initial formulation is. Particularly, the buckling time is quantitatively predicted from the interparticle interactions and shows an excellent agreement with experimental values.