Electron microscopy of gold nanoparticles at atomic resolution

Abstract

Structure determination of gold nanoparticles (AuNPs) is necessary for understanding their physical and chemical properties, and only one AuNP larger than 1 nm in diameter, an Au102NP, has been solved to atomic resolution. Whereas the Au102NP structure was determined by X-ray crystallography, other large AuNPs have proved refractory to this approach. Here we report the structure determination of an Au68NP at atomic resolution by aberration-corrected transmission electron microscopy (AC-TEM), performed with the use of a minimal electron dose, an approach that should prove applicable to metal NPs in general. The structure of the Au68NP was supported by small angle X-ray scattering (SAXS) and by comparison of observed infrared (IR) absorption spectra with calculations by density functional theory (DFT).

Kinetic Monte Carlo approach to Schottky defects in noble metal nanoclusters

“…Recently, three-dimensional imaging of gold clusters [45][46][47][48] has been realized and these may well be model systems for detection of defects in the clusters. One of these references showed the existence of adatoms on gold nanocluster surfaces [44].…”

Aberration-Corrected Electron Microscopy of Nanoparticles

“…An example of a cluster passivized by thiols is shown in Fig. 1 44 , and several others. A new trend has been to produce bimetallic clusters such as of Au-Ag [33,34].…”

Single-particle cryo-EM data acquisition by using direct electron detection camera

“…For many years, it has been known that a modern electron microscope equipped with a field emission gun (FEG) electron source has the capability of delivering images of an inorganic material specimen at atomic resolution [32]. Traditional methods of collecting cryo-EM images had to deal with two major technical limitations.…”