Molecular-Interactions Driven Conjugated Polymer Nanofiber Self-Assembly Toward Greener Fabrication

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Self-assembled conjugated polymer (CP) nanofibers are crucial for efficient charge transport in electronic devices.
• Current methods for forming CP nanofibers from solution lack a generalizable strategy, hindering their widespread application.

Purpose of the Study:

• To establish a molecular-interaction-governed framework for predictable and controllable antisolvent-induced self-assembly of CP nanofibers.
• To enable the rational design of CP nanostructures for advanced electronic applications.

Main Methods:

• Integration of Hansen solubility parameters with a segment-specific affinity descriptor to predict suitable solvent-antisolvent systems.
• Utilizing structural characterization and molecular modeling to understand the role of preaggregate intermediates.
• Validation across diverse polymer systems and solvent-antisolvent combinations.

Main Results:

• A framework was developed that successfully predicts solvent-antisolvent combinations for nanofiber formation.
• Antisolvents with low affinity for polymer alkyl side chains were identified as promoting rigid fibrillar preaggregates, essential for nanofiber growth.
• The method yielded tunable nanofibers (50-200 nm width) and identified eco-friendly terpene-based solvent systems.
• Achieved up to threefold enhancement in field-effect mobility in the resulting CP nanofibers.

Conclusions:

• The presented framework provides a generalizable strategy for controlling conjugated polymer nanostructures.
• This approach facilitates the rational design of nanofibers for sustainable and stretchable electronics.
• The findings pave the way for efficient manufacturing of high-performance CP-based devices.