Chemistry Reference
In-Depth Information
Scheme 4 Synthetic procedure for the synthesis of monodispersed Au
144
(SR)
60
clusters in
methanol. Reprinted from [
114
] with permission by the American Chemical Society
advantage of large solubility difference in acetone, pure Au
144
(SR)
60
can
be separated at a yield of 10-20%. Importantly, this method could be applied
to the syntheses with different thiolate ligands, such as PhC
2
H
4
SH and various
C
n
H
2n+1
SH (where
n
ΒΌ
4-8).
4 Concluding Remarks
In this chapter, we have shown the progress which has been made in recent years in
the study of atomically precise gold nanoclusters. Their synthesis, structural char-
acterization, optical properties, and core size determinations have been described
above. It can be seen that in recent years, various synthetic strategies have been
developed for the synthesis of monodispersed gold nanoclusters with high purity
and high yield. Except for the normally stable clusters (such as Au
144
and Au
25
),
other clusters with a wide range of gold atoms have also been successfully prepared
by chemical processes. The crystal structures of several gold nanoclusters have
been investigated experimentally and theoretically. It is exciting that in recent
years, much attention has been paid to the study of Au-based bimetallic
nanoclusters, which have more promising applications compared to the monome-
tallic clusters. However, despite the great progress made recently for the gold
nanoclusters, several challenges still remain. Firstly, more efficient high-yield
synthetic approaches are expected to be developed to prepare metal clusters with
atomically controlled core composition. Also complicated treatment processes in
the currently reported methods need to be overcome. Secondly, most crystal
structures of gold nanoclusters are not clear at present. The determination of cluster
structure based on single crystals is of vital importance in understanding the
relationship of structure-properties of gold nanoclusters. Thus far, only a few
crystal structures of gold nanoclusters have been unambiguously determinate by
X-ray crystallography, including Au
13
[
64
], Au
25
(SR)
18
[
23
], Au
36
(SR)
24
[
93
],
