Atomically Precise Gold Catalysis - Atomically-Precise Methods for Synthesis of Solid Catalysts - page 89

structures of these clusters with their catalytic and other properties. In re-
cent times, atomically precise gold clusters have been widely investigated
due to their unique properties, which are very different from traditional
nanoparticles.
Initial works on the synthesis of narrowly distributed atomically precise
gold clusters was carried out by Whetten and co-workers through solvent
fractionation process. 11,12 Their method yielded nanoclusters (named as
'Nanocrystal Au Molecules') in the size range of 1-3.5 nm with masses
between 5 and 93 kDa characterized by laser desorption ionization (LDI)
technique. Murray and co-workers have reported on phenylethylthiol-capped
25-atom nanoclusters 13 which were previously mischaracterized as 38-atom
gold nanoclusters. 14 Tsukuda and co-workers reported on the synthesis of a
series of glutathione capped atomically precise gold clusters, which were
separated and purified using polyacrylamide gel electrophoresis (PAGE)
process and characterized using electrospray ionization mass spectroscopy
(ESI-MS). 15 Recently, thiolate-stabilized gold nanoclusters of different sizes
were reported by Jin and co-workers. 16-18 Their group had isolated and
thoroughly investigated the crystal structures, electronic, magnetic and
catalytic properties of thiol-capped Au 25 ,Au 38 ,Au 102 and Au 144 . Their group
was also the first one to report on 'size-focusing' method to achieve atom-
ically precise gold clusters. 19 Figure 4.1 gives a schematic of the synthesis
approaches used to form atomically precise gold cluster catalysts.

d n 9 r 4 n g | 7

.

Figure 4.1 Schematic showing different approaches for synthesis of atomically

precise gold clusters catalysts.