Counting the atoms in supported, monolayer-protected gold clusters.
Mass spectrometry of supported, monolayer-protected, nominally Au(38) (MP-Au(38)) clusters is performed via quantitative High Angle Annular Dark Field-Scanning Transmission Electron Microscopy (HAADF-STEM) using size-selected Au(N) clusters (N = 25, 38, 55) as mass standards. With the intensity due to the (presumed) 24 hexanethiolate ligands taken into account, the clusters are found to contain 38 +/- 2 Au atoms. The method may also be used to determine the degree of aggregation of deposited nanoparticles.
Wang
Z W
ZW
Nanoscale Physics Research Laboratory, School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, United Kingdom.
Toikkanen
O
O
Yin
F
F
Li
Z Y
ZY
Quinn
B M
BM
Palmer
R E
RE