Nanoparticle imaging. Electron microscopy of gold nanoparticles at atomic resolution

Area of Science:

• Nanotechnology
• Materials Science
• Physical Chemistry

Background:

• Understanding gold nanoparticle (AuNP) structure is crucial for their properties.
• Previous atomic-resolution studies were limited to one type of AuNP (Au102NP) using X-ray crystallography.
• Larger AuNPs have been difficult to analyze at atomic resolution.

Purpose of the Study:

• To determine the atomic structure of a gold-68 nanoparticle (Au68NP).
• To establish a new method for atomic-resolution structure determination of metal nanoparticles.
• To overcome the limitations of X-ray crystallography for larger AuNPs.

Main Methods:

• Aberration-corrected transmission electron microscopy (TEM) with minimal electron dose.
• Small-angle X-ray scattering (SAXS) for structural support.
• Density functional theory (DFT) calculations for spectral analysis.

Main Results:

• The atomic structure of the Au68NP was successfully determined.
• The study demonstrates the efficacy of low-dose, aberration-corrected TEM for nanoparticle structure analysis.
• SAXS and DFT calculations corroborated the determined structure.

Conclusions:

• Aberration-corrected TEM provides a viable method for atomic-resolution structure determination of metal nanoparticles.
• This technique expands the scope of structural analysis for nanoparticles beyond X-ray crystallography.
• The findings enable a deeper understanding of nanoparticle physical and chemical properties.