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Stable Open-Shell Polymers via Precise Introduction of Oxygen Radicals with Quinoidal Resonance on Conjugated
1State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, School of Materials Science and Engineering, South China University of Technology, Guangzhou, P. R. China.
Macromolecular Rapid Communications
|June 23, 2026
Summary
Researchers developed new oxygen-rich conjugated radical (ORCR) materials for organic electronics. These stable, high-spin polymers exhibit enhanced photothermal conversion, offering a new design for advanced semiconductor applications.
Area of Science:
- Organic electronics
- Materials science
- Polymer chemistry
Background:
- Classic donor-acceptor (D-A) conjugated polymers are vital in organic electronics but suffer from oxygen sensitivity and low device stability due to aggregation-induced radical (AIR) and ground-state charge transfer (GSCT) phenomena.
- Existing D-A polymers exhibit limitations in air stability and doping sensitivity, hindering their widespread application in organic electronic devices.
Purpose of the Study:
- To design and synthesize novel oxygen-rich conjugated radical (ORCR) materials by incorporating oxygen-centered radicals into D-A polymer backbones.
- To investigate the electronic, photophysical, and stability properties of these new ORCR materials.
- To explore the potential of ORCRs in applications such as photothermal conversion.
Main Methods:
- Synthesis of D-A polymers via atom-economical direct arylation polymerization.
- Post-synthetic dealkylation to generate oxygen-radical polymers.
- Characterization using electron paramagnetic resonance (EPR) spectroscopy.
- Photothermal conversion efficiency testing under laser irradiation.
Main Results:
- The synthesized ORCR polymers exhibit a significantly lowered bandgap and quenched fluorescence, indicating enhanced non-radiative relaxation pathways.
- Electron paramagnetic resonance confirmed high spin concentration and excellent air stability for the ORCR materials.
- A specific polymer, BDTO2-BBT, demonstrated an exceptional photothermal conversion temperature of 170°C under 808 nm laser irradiation, with stable performance over multiple cycles.
Conclusions:
- This study successfully reported robust, open-shell ORCR materials with high spin concentration and remarkable air stability.
- The incorporation of oxygen radicals provides a viable strategy to overcome the stability issues associated with traditional D-A polymers.
- The findings offer a simple yet effective design paradigm for developing stable, high-spin organic radical semiconductors for advanced electronic and photothermal applications.
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