Hydrogen Bonding as a Supramolecular Tool for Robust OFET Devices

Area of Science:

• Materials Science
• Organic Electronics
• Supramolecular Chemistry

Background:

• Organic field-effect transistors (OFETs) are crucial for flexible electronics.
• Small molecules offer tunable properties for OFET applications.
• Hydrogen bonding plays a key role in molecular self-assembly and material properties.

Purpose of the Study:

• To investigate the impact of hydrogen bonding on the semiconducting behavior of a small molecule.
• To evaluate the performance of Boc-protected thiophene-diketopyrrolopyrrole (DPP) and triazatruxene (TAT) based molecules in OFETs.
• To explore the potential of supramolecular networks for efficient organic optoelectronic devices.

Main Methods:

• Synthesis and characterization of Boc-TATDPP and NH-TATDPP molecules.
• Fabrication of OFETs using Boc-TATDPP and NH-TATDPP as semiconducting channels.
• Characterization techniques including TGA, UV/Vis, IR spectroscopy, XRD, and HR-TEM.
• Evaluation of hole mobilities and stability upon blending with PC71BM.

Main Results:

• Annealing Boc-TATDPP at 200°C removed Boc groups, forming a hydrogen-bonded NH-TATDPP network with π-π stacking.
• NH-TATDPP exhibited significantly higher hole mobilities compared to Boc-TATDPP.
• The high hole mobility of NH-TATDPP remained stable even when blended with PC71BM.

Conclusions:

• Hydrogen bonding is a critical factor in enhancing the semiconducting properties of TATDPP-based molecules.
• The robust hydrogen-bonded supramolecular network of NH-TATDPP is promising for developing efficient and stable organic optoelectronic devices.
• Solution-processable Boc-TATDPP offers a convenient route to fabricate NH-TATDPP-based devices.