Atomically Dispersed Cobalt within a Bilayer of C₆₀

Area of Science:

• Materials Science
• Surface Science
• Nanotechnology

Background:

• Fullerenes like C60 are crucial in nanomaterials.
• Controlling atom-molecule interactions at the nanoscale is vital for advanced materials.

Purpose of the Study:

• To investigate the trapping and stable configurations of individual cobalt atoms within a C60 bilayer.
• To understand the atomic-level interactions between cobalt and C60 molecules.

Main Methods:

• Deposition of cobalt atoms onto a C60 double layer supported on graphite.
• High-resolution scanning tunneling microscopy (STM) for atomic imaging.
• Density functional theory (DFT) calculations for structural analysis.

Main Results:

• Observed two stable configurations of single cobalt atoms coordinated with three C60 molecules, denoted as (C60)3Co.
• Demonstrated highly limited diffusion of cobalt atoms within the C60 layers.
• DFT calculations confirmed the Co atom resides in a tetrahedral void between C60 layers.

Conclusions:

• Individual cobalt atoms can be effectively captured in interstitial sites of C60 bilayers.
• The most stable (C60)3Co configuration involves C60 molecules from both layers.
• A less stable configuration with all C60 molecules in the top layer was also identified.