Dresden 2017 – wissenschaftliches Programm
CPP 18.11: Poster
Montag, 20. März 2017, 18:30–21:00, P1C
Assembly of opal balls on superhydrophobic surfaces — •Lucia Baldauf and Laura Rossi — Universiteit van Amsterdam, Amsterdam, The Netherlands
Colloids are particles with at least one dimension in the size range of 1-1000nm. Since their size is comparable to the wavelengths of visible light, periodic structures of colloidal particles can produce materials with interesting optical properties. When these materials consist of silica spheres organized in highly regular close packed structures, we call them opals. In this work, we investigate the crystallization of silica colloids into opals from evaporating droplets on superhydrophobic surfaces [Adv. Mat., 20(22), 4263 (2008); Macromol. Rapid Comm., 31(2), 190 (2010)]. Using superhydrophobic surfaces allows us to induce an isotropic compression of the drying opal balls, rather than introducing a preferential direction by sedimentation under gravity. We study the influence of particle size, shape and surface chemistry on the crystallization process and physical properties of the resulting opals.