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07:32
Reactive Vapor Deposition of Conjugated Polymer Films on Arbitrary Substrates
Published on: January 17, 2018
A spray-processable, low bandgap, and ambipolar donor-acceptor conjugated polymer
Timothy T Steckler1, Xuan Zhang, Jungseek Hwang
1The George and Josephine Butler Polymer Research Laboratory, Department of Chemistry, Center for Macromolecular Science and Engineering, University of Florida, Box 117200, Gainesville, Florida 32611, USA.
Journal of the American Chemical Society
|February 10, 2009
Summary
Researchers developed a novel polymer with the lowest bandgap, enabling solubility and spray processing for organic electronics. This material exhibits ambipolar behavior and four redox states, paving the way for advanced applications.
Area of Science:
- Materials Science
- Organic Electronics
- Polymer Chemistry
Background:
- Development of high-performance organic semiconductors is crucial for advancing electronic devices.
- Soluble and processable polymers are sought after for cost-effective manufacturing.
- Achieving low bandgap energies is key for efficient light absorption and charge transport.
Purpose of the Study:
- To synthesize and characterize a novel polymer with a record-low bandgap.
- To investigate the polymer's solubility, processability, and electronic properties.
- To correlate experimental optical bandgap measurements with theoretical calculations.
Main Methods:
- Synthesis of a polymer combining a strong donor (tris(dodecyloxy)phenyl)-dithieno[3,2-b:2',3'-d]pyrrole and a strong acceptor (4,8-dithien-2-yl-2lambda(4)delta(2)-benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole).
- Optical bandgap estimation using transmission/absorption spectroscopy on single-walled carbon nanotubes (SWCNTs) and reflectance spectroscopy on gold.
- Evaluation of redox states and ambipolar behavior in organic field-effect transistors (OFETs).
Main Results:
- The synthesized polymer exhibits the lowest bandgap (0.5-0.6 eV) for a soluble, spray-processable material to date.
- The polymer demonstrates access to four distinct redox states.
- Ambipolar charge transport was observed in organic field-effect transistors (OFETs).
- Experimental optical bandgap values show good agreement with theoretical calculations.
Conclusions:
- The novel polymer represents a significant advancement in low bandgap, solution-processable organic semiconductors.
- Its unique electronic properties and processability offer potential for next-generation organic electronic devices.
- The study validates the effectiveness of combining specific donor and acceptor units for tailored material properties.
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