la504383m_si_001.pdf (1.16 MB)
Fabrication of Planar Colloidal Clusters with Template-Assisted Interfacial Assembly
journal contribution
posted on 2015-02-10, 00:00 authored by Christopher L. Wirth, Michael De Volder, Jan VermantThe
synthesis of nanoparticle clusters, also referred to as colloidal
clusters or colloidal molecules, is being studied intensively as a
model system for small molecule interactions as well as for the directed
self-assembly of advanced materials. This paper describes a technique
for the interfacial assembly of planar colloidal clusters using a
combination of top-down lithographic surface modification and bottom-up
Langmuir–Blodgett deposition. Micrometer sized polystyrene
latex particles were deposited onto a chemically modified substrate
from a decane–water interface with Langmuir–Blodgett
deposition. The surface of the substrate contained hydrophilic domains
of various size, spacing, and shape, while the remainder of the substrate
was hydrophobic. Particles selectively deposited onto hydrophilic
regions from the decane–water interface. The number of deposited
particles depended on the size of each patch, thereby demonstrating
that tuning cluster size is possible by engineering patch geometry.
Following deposition, the clusters were permanently bonded with temperature
annealing and then removed from the substrate via sonication. The
permanently bonded planar colloidal clusters were stable in an aqueous
environment and at a decane–water interface laden with isotropic
colloidal particles. The method is a simple and fast way to synthesize
colloidal clusters with few limitations on particle chemistry, composition,
and shape.