Surface Single-Atom Tailoring of a Gold Nanoparticle.

Area of Science:

• Nanomaterials Science
• Inorganic Chemistry
• Surface Chemistry

Background:

• Controlled modification of nanoparticle surfaces at the atomic level is a significant challenge.
• Previous research has not achieved site-specific single-atom manipulation on gold nanoparticles.

Purpose of the Study:

• To report the first successful introduction of a single sulfur atom onto a gold nanoparticle surface.
• To investigate the structural and photoluminescent consequences of this surface atom tailoring.

Main Methods:

• Single-crystal X-ray crystallography was employed to determine the precise structure of the modified nanoparticle.
• Synthesis of the sulfur-tailored gold nanoparticle (Au60S7(SCH2Ph)36).

Main Results:

• A single sulfur atom was successfully introduced onto the surface of the Au60S6(SCH2Ph)36 nanoparticle, forming Au60S7(SCH2Ph)36.
• The introduced sulfur atom was tetrahedrally coordinated (μ4-S) within an unprecedented Au23S4(SCH2Ph)18 motif.
• The modification altered the internal structure and crystallographic arrangement from 6HLH to "ABAB" packing.
• Enhanced solid photoluminescence with a slight redshift in emission was observed.

Conclusions:

• The controlled introduction of a single surface atom on gold nanoparticles is now achievable.
• The sulfur atom's incorporation significantly impacts nanoparticle structure and optical properties.
• The enhanced photoluminescence, particularly in the near-infrared region, suggests potential applications in anticounterfeiting and imaging.