Highly ordered C60 monolayer self-assembled by using an iodine template on an Au(111) surface in solution

Area of Science:

• Surface Science
• Materials Chemistry
• Nanotechnology

Background:

• Gold (Au) surfaces are crucial in catalysis and electronics.
• Fullerenes (C60) exhibit unique electronic and structural properties.
• Surface modification is key to controlling molecular self-assembly.

Purpose of the Study:

• To investigate the self-organization of C60 on an iodine-modified Au(111) surface.
• To understand the role of iodine in controlling C60 adlayer structure and molecular imaging.
• To explore the effect of iodine removal on the C60 adlayer.

Main Methods:

• Preparation of an iodine-modified Au(111) substrate.
• Self-assembly of C60 from a benzene solution.
• Imaging of C60 adlayers using techniques like Scanning Tunneling Microscopy (STM).
• Electrochemical reduction for iodine desorption.

Main Results:

• A highly ordered C60 adlayer was successfully formed on I/Au(111).
• Two distinct C60 lattice structures, (2√3 × 2√3)R30° and p(2×2), were observed.
• Molecular symmetry/asymmetry relative to iodine influenced C60 rotation and intramolecular imaging.
• Iodine desorption preserved C60 ordering but eliminated intramolecular patterns.

Conclusions:

• The I/Au(111) surface acts as a template for ordered C60 self-assembly.
• Iodine's interaction with C60 dictates the observed adlayer structures and imaging resolution.
• The presence of iodine is essential for visualizing the internal structure of C60 molecules on this surface.