Single-Atom Tuning of Structural and Optoelectronic Properties in Halogenated Anthracene-Based Covalent Organic
Klaudija Paliušytė1, Laura Fuchs2, Zehua Xu1
1Department of Chemistry and Center for NanoScience (CeNS), University of Munich (LMU), Munich 81377, Germany.
ACS Omega
|June 8, 2026
Summary
Single-atom halogen substitution precisely tunes the optoelectronic properties of covalent organic frameworks (COFs). This molecular design approach offers a powerful method for controlling material structure and optical responses in functional materials.
Area of Science:
- Materials Science
- Organic Chemistry
- Solid-State Physics
Background:
- Rational design of functional materials requires tuning structural and optoelectronic properties.
- Covalent organic frameworks (COFs) are versatile platforms for advanced material applications.
Purpose of the Study:
- To investigate the impact of single-atom halogen substitution on the optoelectronic properties of π-extended anthracene-based COFs.
- To establish a molecular design strategy for precise control over COF properties.
Main Methods:
- Synthesis of imine-linked COFs (W-A-X) using a Wurster-type amine and halogenated anthracene dialdehydes (H, Cl, Br, I).
- Characterization using UV-vis absorption, photoluminescence spectroscopy, and time-dependent density functional theory (TD-DFT) calculations.
- Analysis of framework formation and excited-state dynamics.
Main Results:
- Halogen substitution significantly influences COF crystalline domain size, with brominated COFs showing larger domains.
- A systematic redshift in optical response (H < Cl < Br < I) was observed with increasing halogen atomic number.
- Chlorine substitution (W-A-Cl) led to a longer excited-state lifetime, indicating strengthened donor-acceptor interactions.
Conclusions:
- Single-atom halogen substitution is a powerful and modular tool for tailoring the structural and optical properties of anthracene-based COFs.
- Halogen-induced changes in band structure mechanistically explain the observed optoelectronic property trends.
- This approach enables precise control over the optoelectronic behavior of functional COFs.
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