Free Valence Electron Centralization Strategy for Preparing Ultrastable Nanoclusters and Their Catalytic Application

Area of Science:

• Nanotechnology
• Materials Science
• Catalysis

Background:

• Silver nanoclusters offer precise structures and unique properties but lack the stability of gold counterparts.
• Limited thermal stability of silver nanoclusters hinders their practical applications.
• Developing stable silver nanoclusters is crucial for advancing nanotechnology and catalysis.

Purpose of the Study:

• To enhance the thermal stability of silver nanoclusters using a free valence electron centralization strategy.
• To investigate the structural and electronic effects of alloying silver nanoclusters with copper and gold.
• To explore the catalytic performance of the enhanced nanoclusters in high-temperature reactions.

Main Methods:

• Controlled alloying of parent silver nanoclusters (Ag29) with copper and gold to form Ag17Cu12 and Au1Ag16Cu12 nanoclusters.
• Structural determination using single-crystal X-ray diffraction.
• Investigation of electronic properties and stability enhancement mechanism using X-ray photoelectron spectroscopy and density functional theory calculations.
• Evaluation of catalytic activity in multicomponent A3 coupling reactions.

Main Results:

• The trimetallic Au1Ag16Cu12 nanocluster exhibited ultrastability up to 175 °C.
• Structural analysis confirmed the precise atomic arrangement in the alloyed nanoclusters.
• Free valence electron centralization to the nanocluster core was identified as the key factor for enhanced stability.
• The Au1Ag16Cu12 nanocluster dramatically reduced the reaction time for A3 coupling from 5 hours to 3 minutes.

Conclusions:

• A novel strategy of free valence electron centralization effectively enhances the thermal stability of silver nanoclusters.
• Alloying with copper and gold creates ultrastable trimetallic nanoclusters with potential for high-temperature applications.
• The enhanced nanoclusters demonstrate significant improvements in catalytic efficiency, offering a pathway for faster chemical synthesis.