Dodecatwistarene Imides with Zigzag-Twisted Conformation for Organic Electronics

Area of Science:

• Organic Chemistry
• Materials Science
• Nanotechnology

Background:

• 1D nonplanar graphene nanoribbons typically adopt helical, zigzag, or mixed conformations.
• Controlling the conformation of nanoribbons is crucial for their electronic properties.

Purpose of the Study:

• To synthesize and characterize a new class of 1D nonplanar graphene nanoribbons with a unique twisted topology.
• To investigate the conformational stability and electronic properties of these novel nanoribbons.

Main Methods:

• Bottom-up synthesis utilizing palladium-catalyzed Stille coupling and C-H activation.
• Single-crystal X-ray diffraction analysis to determine molecular structure and conformation.
• Fabrication and testing of organic field-effect transistors (OFETs).

Main Results:

• Successfully synthesized dodecatwistarene imides, featuring twelve linearly fused benzene rings.
• Observed a stable zigzag-twisted conformation (pendulum angle of 53°) due to steric hindrance, resistant to thermal conversion up to 250°C.
• OFETs based on these nanoribbons demonstrated electron mobility of 1.5 cm²/V·s after annealing.

Conclusions:

• Dodecatwistarene imides represent a new class of conformationally stable, twisted 1D nanoribbons.
• The stable twisted structure does not impede charge transport, showing potential for organic electronic applications.
• This work provides a pathway for designing novel graphene nanostructures with tailored electronic properties.