Silvery fullerene in Ag₁₀₂ nanosaucer

Area of Science:

• Nanoscale Science
• Materials Chemistry
• Inorganic Chemistry

Background:

• Fullerenes, like C60, are carbon cage molecules with unique structures.
• Synthesizing small fullerenes and their non-carbon counterparts, such as silver fullerenes, remains experimentally challenging.
• Previous research identified the first all-gold fullerene, Au32, highlighting the pursuit of similar silver structures.

Purpose of the Study:

• To report the experimental isolation and characterization of a novel silver nanocluster (NC) with a fullerene kernel.
• To investigate the structural and electronic properties of this silver fullerene.
• To evaluate the photothermal conversion efficiency of the synthesized nanocluster.

Main Methods:

• Synthesis and isolation of a 102-nuclei silver nanocluster (Ag102).
• Structural determination of the Ag102 nanocluster, revealing a Ag32 fullerene kernel encapsulated within a Ag70 shell.
• Characterization of the passivation layer, (KPO4)10, and surface ligands (BuPhS- and CF3COO-).
• Measurement of photothermal conversion efficiency across the visible to near-infrared spectrum.

Main Results:

• A flying saucer-shaped Ag102 nanocluster was successfully synthesized, featuring a Ag32 silvery fullerene kernel (Ag12@Ag20).
• The Ag32 kernel is stabilized by a robust cyclic anionic layer of (KPO4)10, which also templates the outer Ag70 shell.
• Ligands (BuPhS- and CF3COO-) exhibited regioselective arrangement on the silver shell.
• Ag102 demonstrated high photothermal conversion efficiency (η = 67.1% ± 0.9% at 450 nm, 60.9% ± 0.9% at 660 nm, 50.2% ± 0.5% at 808 nm).

Conclusions:

• This study reports the capture of silver kernels with the topology of the smallest fullerene, C20.
• The findings provide a new method for incorporating alkali metals into coinage metal nanoclusters using M-oxoanions.
• The excellent photothermal properties of Ag102 suggest its potential for applications in photothermal conversion and remote laser ignition.