Intra- and intermolecular self-assembly of a 20-nm-wide supramolecular hexagonal grid

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Nanotechnology

Background:

• Coordination-driven self-assembly has advanced 3D structures but struggled with large, discrete 2D architectures.
• Synthesizing metallo-supramolecular systems with controlled shapes and sizes (10-100 nm) remains a significant challenge.

Purpose of the Study:

• To report the successful construction of giant supramolecular hexagonal grids.
• To overcome limitations in creating large, discrete 2D supramolecular architectures.

Main Methods:

• Utilized a combination of intra- and intermolecular metal-mediated self-assembly steps.
• Employed scanning tunnelling microscopy (STM) for submolecular resolution imaging of intermediates and final architectures.
• Applied scanning tunnelling spectroscopy (STS) for atomic-scale characterization.

Main Results:

• Successfully constructed giant supramolecular hexagonal grids with diameters around 20 nm and molecular weights exceeding 65 kDa.
• Identified and characterized fourteen distinct hexagonal grid isomers at the atomic scale.
• Demonstrated the ability to image hexagonal intermediates and final grid structures with submolecular resolution using STM.

Conclusions:

• This work presents a significant advancement in the synthesis of large, discrete 2D supramolecular architectures.
• The developed methods enable precise control over the formation and characterization of complex metallo-supramolecular systems.
• The findings open new avenues for designing and fabricating nanoscale materials with tailored properties.