Gold clusters assembled homochiral helical microbowties.

Area of Science:

• Supramolecular chemistry
• Nanotechnology
• Chiral materials science

Background:

• Hierarchical chiral architectures are crucial in nature, but fabricating microscale helical superstructures from metal clusters is challenging.
• Understanding the evolution of chirality in complex structures is vital for advanced material design.

Purpose of the Study:

• To develop a method for fabricating microscale helical superstructures from metal clusters.
• To investigate the mechanism of chirality transfer and hierarchical assembly in these structures.
• To explore the optical properties of the resulting helical microbowties.

Main Methods:

• Electrostatic interaction-driven co-assembly of chiral gold (Au₄) clusters and trans-1,4-cyclohexanediamine.
• Characterization of morphology evolution from nanoplatelets to helical microbowties.
• Analysis of photoluminescence and circularly polarized luminescence.

Main Results:

• Successfully fabricated hierarchically assembled helical bowties with micrometer scale.
• Demonstrated continuous chirality transfer from Au₄ clusters to the microstructures.
• Elucidated the hierarchical evolution mechanism involving helical stacking and twisting.
• Observed switchable photoluminescence and circularly polarized luminescence.

Conclusions:

• Achieved controllable formation of metal cluster-based helical microbowties.
• Deepened the understanding of chirality transfer and expression at the microscale.
• Highlighted the potential of these structures for applications in optics and chiral materials.