Self-Assembled Ring-Based Complex Colloidal Particles by Lock-And-Key Interaction and Their Self-Assembly into...

Area of Science:

• Colloid and Surface Science
• Materials Science
• Crystallography

Background:

• Creating hierarchical crystalline materials from simple colloids is challenging due to non-hierarchical colloidal interactions.
• Existing methods struggle to achieve complex hierarchical structures without controlled assembly pathways.

Purpose of the Study:

• To present a novel hierarchical self-assembly (SA) route for fabricating complex colloidal building blocks.
• To demonstrate the formation of unusual hierarchical colloidal liquid crystals and crystals using these building blocks.

Main Methods:

• Employing colloidal rings and anisotropic colloidal particles to form complex colloids.
• Designing hierarchical SA driving forces controlled by colloidal shape and shape-dependent depletion attraction.
• Utilizing depletion-induced lock-and-key interactions for efficient loading of particles into rings (>90% efficiency).

Main Results:

• High-quality building blocks were produced by efficiently loading spheres, spherocylinders, and oblate ellipsoids into colloidal rings.
• Second driving forces, such as higher volume fraction or stronger depletion attraction, enabled SA into ordered superstructures.
• Unusual hierarchical colloidal (liquid) crystals were successfully fabricated, overcoming previous fabrication difficulties.

Conclusions:

• The developed hierarchical SA route offers a promising strategy for constructing unprecedented crystalline materials.
• This method advances the field of hierarchical SA by enabling the creation of complex structures previously unattainable.
• The findings pave the way for designing and synthesizing novel hierarchical materials with tailored properties.