Colloidal nanocrystal synthesis and the organic-inorganic interface
“Colloidal Nanocrystal Synthesis and the Organic-Inorganic Interface
After synthesis, the organic pigmentmicronanocrystals were isolated by adding cyclohexane in a volumeratio of 3:1 to the crude colloidal solutions, followed by centrifugation(relative centrifugal force = 14.100 g, 5 min) and redispersion inchloroform. The washing step was repeated four times before the micronanocrystalswere stored in chloroform or in chlorobenzene.
Colloidal nanocrystal synthesis and the organic–inorganic interface.
This paper provides an overview of the
synthetic techniques used to prepare colloidal
nanocrystals (NC) of controlled composition,
size, shape, and internal structure and the
methods for manipulation of these materials
into ordered NC assemblies (superlattices).
High-temperature solution-phase synthesis
(100–300°C) is followed by size-selective
separation techniques in the preparation of
monodisperse NC samples tunable in size
from1 to 15 nm in diameter with5%
standard deviation. Each NC consists of a
crystalline inorganic core coordinated by an
organic monolayer. These monodisperse
NC samples enable systematic studies of
structural, electronic, magnetic, and optical
properties of materials as a function of size
evolution from molecular species (100 atoms)
to bulk solids (1 atoms). We illustrate
size-dependent properties for magnetic
materials using Co and for semconducting
materials using PbSe. These NC samples are
sufﬁciently uniform in size to self-assemble
into close-packed, ordered NC superlattices,
also known as colloidal crystals.