Programmable Nanostructural Orientation on Amorphous Phase-Separating Systems

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Controlling nanostructural orientation in bottom-up self-assembly, particularly in amorphous phase-separating systems, is challenging.
• Orientation in these systems is typically governed by interfacial energy, which is difficult to control dynamically.

Purpose of the Study:

• To develop a photo-programmable strategy for controlling nanostructural orientation in amorphous phase-separating systems.
• To demonstrate this strategy using amorphous block copolymers as a model system.

Main Methods:

• Designing a persulfurated aromatic modulator that interacts with both polymer domains.
• Utilizing light irradiation to induce photo-aggregation and redistribute the modulator.
• Analyzing the resulting changes in interfacial energy and self-assembled nanostructure orientation.

Main Results:

• The modulator initially minimizes interfacial energy mismatch, favoring perpendicular nanostructure orientation.
• Light irradiation causes modulator aggregation, amplifying interfacial energy asymmetry and driving parallel orientation.
• The orientation switching is reversible upon light removal.

Conclusions:

• This photo-programmable strategy offers dynamic control over nanostructure orientation in amorphous systems.
• The method enables density multiplication of nanostructures and can serve as a template for incorporating other materials, like conductive polymers.
• This approach expands functional capabilities in practical nanotechnology.