Chemistry Reference
In-Depth Information
Gold Thiolate Nanomolecules: Synthesis,
Mass Spectrometry, and Characterization
Chanaka Kumara, Vijay Reddy Jupally, and Amala Dass
Abstract This chapter summarizes the synthetic routes used for the following
HS-CH
2
-CH
2
-Ph protected gold nanoclusters: Au
25
(SR)
18
,Au
38
(SR)
24
,Au
40
(SR)
24
,
Au
67
(SR)
35
,Au
103-105
(SR)
45-46
,Au
130
(SR)
50
,andAu
144
(SR)
60
. The synthetic routes
are based on either (a) direct synthetic route or (b) a core-size conversion route. The
synthetic routes leading to the most stable clusters are discussed and the character-
izational techniques used to study the products are described.
Keywords Clusters
Electrospray
Gold
MALDI
Nanoclusters
Nanomolecules
Nanoparticle mass spectrometry
Thiolated
Contents
1 Introduction .................................................................................. 156
2 Overview of Various Thiolated Gold Nanomolecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
2.1 Ultra-Stable Nanomolecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
2.2 Meta-stable Nanomolecules .......................................................... 157
3 Synthetic Routes: Direct Synthesis vs. Core-Size Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
3.1 Techniques Used to Study the Synthesis Reaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
3.2 Historical Introduction to the Synthesis of Nanomolecules . . . . . . . . . . . . . . . . . . . . . . . . . 158
4 Direct Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
4.1 Ultra-Stable Nanomolecules: Au
25
(SR)
18
,Au
144
(SR)
60
, and Its Au-Ag alloys . . . . 159
4.2 Meta-Stable Nanomolecules: Au
67
(SR)
35
and Au
103-105
(SR)
45-46
.................. 166
5 Synthesis Through Core-Size Conversion .................................................. 170
5.1 Core-Size Conversion Synthesis of Au
38
(SR)
24
and Au
40
(SR)
24
................... 171
5.2 Core-Size Conversion Synthesis of Au
38-
x
Ag
x
(SR)
24
Alloys ........................ 177
5.3 Core-Size Conversion Synthesis of Au
130
(SR)
50
and Its Alloys . . .................. 179
6 Summary ..................................................................................... 183
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
