Chemistry Reference
In-Depth Information
Fig. 2 (A) Schematic diagram of synthesis of gold nanoclusters from the Au
11
(PPh
3
)
8
Cl
3
cluster
precursor 1. Synthesis conditions: (
a
) Ligand exchange of 1 in CHCl
3
at 55
C with excess
octadecanethiol produces the thiol-stabilized particle 2;(
b
) Interfacial (CHCl
3
/H
2
O) ligand
exchange of 1 at 55
C with (
N
,
N
-dimethylamino)ethanethiol hydrochloride produces the cationic
thiol-stabilized particle 3 in a single step; (
c
) Interfacial (CHCl
3
/H
2
O) ligand exchange of 1 at
55
C with sodium 2-mercaptoethanesulfonate (MESA) produces the anionic particle 4, which
contains a mixed ligand shell; (
d
) Treatment of 4 with excess MESA in 1:1 THF/H
2
O yields
particle 5 containing only MESA in the ligand shell. (B) UV-Vis spectra of the gold precursor and
the formed nanoclusters through ligand exchange process as described in A.(
a
) precursor cluster 1;
(
b
) cluster 2;(
c
) cluster 3;(
d
) cluster 5. Reprinted from [
58
] with permission by the American
Chemical Society
protected by 4, 4, 4-phosphinidynetri(benzenemethanamine). However, these
clusters are normally not stable and are prone to oxidative decomposition when
exposed to ambient conditions. In order to overcome such problem, Hutchison and
coworkers [
58
] synthesized stable Au
11
nanoclusters protected by alkanethiols
through an exchange-reaction process. As shown in Fig.
2A
, such ligand exchange
strategy could be applied to the preparation of different
thiol-stabilized Au
