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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Chiral BN-Heteroacenes Embedded with B←N Coordination: Acid-Triggered Reversible Bond Switching and Optical Limiting
Wenlong Zhao1, Hongxiang Zhang1, Shitao Wang2
1Research Center for Free Radical Chemistry, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Tianshui Southern Road 222, Lanzhou 730000, Gansu Province China.
ACS Applied Materials & Interfaces
|August 8, 2025
Summary
Chiral heteroacenes with boron-nitrogen coordination bonds were synthesized and exhibit tunable optoelectronic properties. These novel materials show potential for advanced applications in optical limiting and circularly polarized luminescence.
Area of Science:
- Materials Science
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Boron-nitrogen coordination (B←N) bonds are key for designing π-conjugated systems.
- Tuning optoelectronic properties of materials is crucial for advanced applications.
Purpose of the Study:
- Synthesize and characterize novel chiral heteroacenes featuring B←N bonds.
- Investigate their optoelectronic properties, including luminescence and nonlinear optical responses.
- Explore the potential of these materials for optical limiting applications.
Main Methods:
- Four-step synthesis approach for chiral heteroacenes (5a-5c).
- Crystal structure analysis to determine molecular architecture.
- Chiral-phase High-Performance Liquid Chromatography (HPLC) for enantiomeric separation.
- Circular Dichroism (CD) spectroscopy for characterization.
- Absorption and emission spectroscopy to study optoelectronic properties.
Main Results:
- Successful synthesis of chiral heteroacenes (5a-5c) with B←N coordination within twisted π-frameworks.
- Demonstrated intrinsic chirality and successful resolution into enantiomers.
- Observed circularly polarized luminescence (CPL) with luminescence dissymmetry factors (g_lum) up to 10⁻³.
- Induced strong intramolecular charge-transfer (ICT) transitions with low-energy absorption (420-600 nm).
- Reversible modulation of ICT band via acid-base treatment.
- Exhibited strong third-order nonlinear optical (NLO) responses.
Conclusions:
- B←N-embedded chiral heteroacenes are versatile building blocks for multifunctional materials.
- These compounds possess tunable optoelectronic properties and CPL capabilities.
- Potential applications in optical limiting and stimuli-responsive devices are highlighted.
Keywords:
B←N dative bondChiral conjugated polycyclesCircularly polarized luminescenceMultiheteroatom dopingOptical limiting materialsMore Related Videos
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