CO₂ Responsive Thin-Film Transistors Using Conjugated Polymer Complexes with Single-Walled Carbon Nanotubes

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Conjugated polymers are crucial in organic electronics.
• Single-walled carbon nanotubes (SWNTs) offer unique electronic properties.
• Developing novel sensors requires functionalized materials with specific interactions.

Purpose of the Study:

• To synthesize a conjugated polyfluorene polymer functionalized with amidine groups.
• To create polymer-nanotube complexes with SWNTs.
• To investigate the CO2-responsiveness of these complexes for sensor applications.

Main Methods:

• Copper-catalyzed azide-alkyne cycloaddition for polymer functionalization.
• Formation of supramolecular interactions between functionalized polyfluorene and SWNTs.
• Fabrication of thin-film transistor (TFT) devices using polymer-SWNT complexes.

Main Results:

• Synthesized polymer formed soluble complexes with SWNTs via supramolecular interactions.
• Complexes exhibited reversible precipitation and redissolution in response to CO2 and N2.
• Incorporation into TFTs resulted in a CO2-responsive sensor with a reversible threshold voltage shift and on-current decrease.

Conclusions:

• Functionalized conjugated polymers wrapped around SWNTs can act as active layers in SWNT-based TFT sensors.
• The amidine groups provide CO2 sensitivity, enabling reversible sensing mechanisms.
• This approach offers a pathway for developing advanced, functional SWNT-based electronic devices.