Field-directed of patchy anisotropic microparticles with defined shape.

TitleField-directed of patchy anisotropic microparticles with defined shape.
Publication TypeJournal Article
Year of Publication2013
AuthorsCW Shields, S Zhu, Y Yang, B Bharti, J Liu, BB Yellen, OD Velev, and GP López
JournalSoft Matter
Volume9
Issue38
Start Page9219
Pagination9219 - 9229
Date Published09/2013
Abstract

Electromagnetic fields can generate orientation-dependent, long range interactions between colloidal components that direct their into highly ordered structures, such as small ordered clusters, chains, and large crystalline lattices. While much effort has been devoted to exploring the assembly of spherical colloids, few reports have investigated the directed assembly of non-spherical particles with Janus or patchy morphologies. Here, we use photolithographic techniques to fabricate a wide range of anisotropically shaped patchy particles and follow their in liquid suspensions under the influence of electric and magnetic fields. We analyze the assembly of several types of patchy particles across a range of field parameters and fluid compositions, and report a number of distinct, well-ordered, architectures including cylindrical, prismatic, and staggered chains. The structures assembled from anisotropic patchy components provide a glimpse into the range of architectures that can be created by combining field directed with rationally designed particles. By using numerical simulations to model the electric and magnetic field interactions between these particles, we interpret the results of the assembly process and explain how they can be controlled by the position of the metal facet, the frequency (for AC fields), or magnetic susceptibility of the medium. The resulting structures, and similar ones produced through the field-directed assembly of patchy anisotropic particles, can possess unique electrical and optical properties and may have potential applications in a number of future technology applications such as microactuators, metamaterials and multiferroic materials.

DOI10.1039/c3sm51119g
Short TitleSoft Matter