A Donor-Acceptor-Type Two-Dimensional Poly(Arylene Vinylene) for Efficient Electron Transport and Sensitive...

Area of Science:

• Materials Science
• Polymer Chemistry
• Organic Electronics

Background:

• Two-dimensional (2D) conjugated polymers and frameworks are promising for electronics and photocatalysis.
• Challenges include narrow optical band gaps and inefficient electron transport in these materials.
• 2D poly(arylene vinylene)s (2D PAVs) are a key class of these emerging materials.

Purpose of the Study:

• To synthesize a novel donor-acceptor type 2D PAV with improved electronic and optical properties.
• To investigate the charge transport characteristics of the new material.
• To evaluate its potential for gas sensing applications, specifically for sulfur dioxide (SO2).

Main Methods:

• Synthesis of 2DPAV-TBDT-IT via an Aldol-type 2D polycondensation.
• Optical band gap measurement.
• Density functional theory (DFT) calculations for charge transport analysis.
• Terahertz spectroscopy to determine charge mobility.
• Fabrication of chemiresistors for gas sensing.

Main Results:

• The synthesized 2DPAV-TBDT-IT exhibits the smallest optical band gap (1.15 eV) among reported 2D conjugated polymers.
• DFT calculations revealed electron-dominating transport with a small effective electron mass.
• Terahertz spectroscopy showed a high charge mobility of 26 cm² V⁻¹ s⁻¹.
• Chemiresistors demonstrated ultrasensitive SO2 detection with a limit of detection of 0.088 ppb.

Conclusions:

• 2DPAV-TBDT-IT represents a significant advancement in 2D conjugated polymers, offering a narrow band gap and efficient electron transport.
• The material's properties make it highly suitable for next-generation electronic and photocatalytic devices.
• Its high electron deficiency and transport characteristics enable superior performance in chemiresistive gas sensing.