Naphthodithiophene-Based Donor-Acceptor Polymers: Versatile Semiconductors for OFETs and OPVs

Area of Science:

• Organic electronics
• Materials science
• Polymer chemistry

Background:

• Developing high-performance semiconducting polymers is crucial for advancing organic electronics.
• Donor-acceptor (D-A) polymers offer tunable electronic properties.
• Naphthodithiophene (NDT3) is a novel building block for polymer design.

Purpose of the Study:

• To synthesize and characterize novel naphthodithiophene (NDT3)-based donor-acceptor semiconducting polymers.
• To investigate the structure-property relationships, focusing on π-π stacking and electronic performance.
• To evaluate their potential for organic field-effect transistors (OFETs) and organic photovoltaics (OPVs).

Main Methods:

• Synthesis of a series of NDT3-based D-A polymers.
• Characterization using techniques such as NMR, GPC, UV-Vis, and cyclic voltammetry.
• Device fabrication and characterization for OFET mobility and OPV power conversion efficiency (PCE).

Main Results:

• The synthesized polymers exhibited very close π-π stacking (3.5 Å) due to their large π system and D-A structure.
• The polymer PNDT3NTz-DT demonstrated excellent versatility, achieving a field-effect mobility of ~0.5 cm²/ (V s) and a PCE of ~5%.
• These properties position NDT3 as a promising core unit for high-performance semiconducting polymers.

Conclusions:

• NDT3 is a versatile core unit for designing high-performance semiconducting polymers.
• The strategy of using highly π-extended heteroarenes as both donor and acceptor units is effective.
• The developed polymers show significant potential for applications in OFETs and OPVs.