Evolution of thiolate-stabilized Ag nanoclusters from Ag-thiolate cluster intermediates

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Thiolate-stabilized silver (Ag) nanoclusters are of significant research interest.
• The formation mechanism of these nanoclusters is not well understood.

Purpose of the Study:

• To elucidate the formation mechanism of thiolate-stabilized silver nanoclusters.
• To investigate the reaction intermediates during the synthesis process.

Main Methods:

• Electrospray ionization mass spectrometry (ESI-MS) was used to monitor reaction intermediates.
• Sodium-borohydride reduction of silver 4-tert-butylbenzenethiolate (AgSPh-tBu) was studied.

Main Results:

• A novel evolution route mediated by Ag-thiolate clusters was identified.
• Intermediate Ag-thiolate clusters transform into specific nanoclusters like Ag17(SPh-tBu)12^3- and Ag44(SPh-tBu)30^4-.
• The size of initial Ag-thiolate clusters dictates the reaction pathway.

Conclusions:

• The study reveals a new mechanism for thiolate-stabilized silver nanocluster synthesis.
• This mechanism differs from traditional bottom-up approaches, offering new insights.
• The findings are applicable to other silver thiolate precursors, such as AgSPhMe2.