Complex assembly from planar and twisted π-conjugated molecules towards alloy helices and core-shell structures

Area of Science:

• Materials Science
• Organic Chemistry
• Nanotechnology

Background:

• Controlled integration of dissimilar π-conjugated molecules into complex topological configurations is challenging.
• Organic semiconductors exhibit diverse assembly features, complicating co-assembly.

Purpose of the Study:

• To investigate the co-assembly of structurally similar organic semiconductors.
• To achieve controlled formation of complex topological configurations using two different molecules.
• To explore the creation of organic alloy structures and core-shell architectures.

Main Methods:

• Co-assembly of 9,10-bis(phenylethynyl)anthracene (BA) and 5,12-bis(phenylethynyl)naphthacene (BN) was controlled by growth kinetics and molar ratio.
• Solute exchange process was employed to create core-shell structures.

Main Results:

• Two-component helices of BA and BN were successfully formed, acting as (BA)_x(BN)_1-x alloys due to compatible structures.
• Epitaxial growth of an alloy layer on a BA tube resulted in a BA@(BA)_x(BN)_1-x core-shell structure.
• Precise control over composition and morphology of these organic nanostructures was demonstrated.

Conclusions:

• Compatible structural relationships between similar organic molecules facilitate controlled co-assembly.
• The study demonstrates a method for creating complex organic nanostructures with tunable composition and morphology.
• This work advances the understanding of co-assembly principles for materials with similar structures.