[19]Starphene: Combined In-Solution and On-Surface Synthesis Towards the Largest Starphene

Area of Science:

• Organic Chemistry
• Materials Science
• Nanotechnology

Background:

• Starphenes are three-fold symmetric polycyclic aromatic compounds with potential applications in molecular electronics and nanotechnology.
• Large, unsubstituted starphenes are difficult to synthesize due to poor solubility and high reactivity.

Purpose of the Study:

• To develop synthetic strategies for creating larger starphene molecules.
• To synthesize and characterize the largest starphene to date, featuring 19 cata-fused benzene rings in three hexacene branches.

Main Methods:

• Employed a combination of solution-phase and on-surface synthesis techniques.
• Utilized high-resolution scanning tunneling microscopy (STM) and spectroscopy (STS) for characterization.

Main Results:

• Successfully synthesized the largest starphene reported to date.
• Characterization revealed a small HOMO-LUMO transport gap of 0.9 eV, indicating potential for electronic applications.

Conclusions:

• The developed synthetic strategies enable the creation of large starphene structures.
• The synthesized starphene's electronic properties make it a promising candidate for molecular electronics and nanotechnology.