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Arylboron Tetraphenylethylene-Analog AIEgens Enabling Reversible Closed-Shell/Open-Shell Switching
Haoyu Gao1, Yan Tang1, Pengchao Liu2
1College of Chemistry and Materials, Henan Agricultural University, Zhengzhou 450002, P. R. China.
Journal of the American Chemical Society
|July 2, 2026
Summary
Researchers developed new molecules with aggregation-induced emission (AIE) properties. These materials show tunable light emission and can switch electronic states, enabling advanced optical applications.
Area of Science:
- Materials Science
- Organic Chemistry
- Photophysics
Background:
- Aggregation-induced emission (AIE) systems face challenges in integrating emission control with reversible electronic switching.
- Balancing restriction of intramolecular motion (RIM) and spin delocalization is key for advanced AIE functionalities.
Purpose of the Study:
- To design and investigate arylboron-functionalized tetraphenylethylene-analog molecules for controlled AIE.
- To explore the RIM-governed AIE mechanism using a rotor-locking strategy.
- To achieve reversible electronic-state switching for optoelectronic applications.
Main Methods:
- Synthesis of arylboron-functionalized tetraphenylethylene-analog molecules.
- Systematic investigation of structure-property relationships.
- Electrochemical reduction to generate boron-olefin radicals.
- Characterization of optical and electronic properties.
Main Results:
- Demonstrated a RIM-governed AIE mechanism via rotor-locking.
- Achieved pronounced AIE activity and reversible mechano-/piezochromic responses.
- Generated stable boron-olefin radicals with broadband absorption (visible to NIR-II).
- Enabled electrochromic switching between closed- and open-shell states with high optical contrast and fast response.
Conclusions:
- Rotor positioning is crucial for controlling conformational freedom and emission in AIE systems.
- The developed molecules offer a platform for tunable AIE and reversible electrochromism.
- Potential applications include smart displays, smart windows, and light-adaptive systems.
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