title: Pressure-controlled formation of crystalline, Janus, and core-shell supraparticles.
abstract: Binary mixtures of nanoparticles self-assemble in the confinement of evaporating oil droplets and form regular supraparticles. We demonstrate that moderate pressure differences on the order of 100 kPa change the particles' self-assembly behavior. Crystalline superlattices, Janus particles, and core-shell particle arrangements form in the same dispersions when changing the working pressure or the surfactant that sets the Laplace pressure inside the droplets. Molecular dynamics simulations confirm that pressure-dependent interparticle potentials affect the self-assembly route of the confined particles. Optical spectrometry, small-angle X-ray scattering and electron microscopy are used to compare experiments and simulations and confirm that the onset of self-assembly depends on particle size and pressure. The overall formation mechanism reminds of the demixing of binary alloys with different phase diagrams.
authors.affiliation: INM - Leibniz Institute for New Materials, Campus D2 2, 66123 Saarbrücken, Germany. tobias.kraus@leibniz-inm.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kister
authors.forename: Marko
authors.initials: M
authors.lastname: Mravlak
authors.forename: Tanja
authors.initials: T
authors.lastname: Schilling
authors.forename: Tobias
authors.initials: T
authors.lastname: Kraus