Towards high-performance nonlinear optical materials through embedding a D-A system into β-ketoenamine-linked COFs.
Mingyan Li1, Jiahui Chu1, Debo Ding1
1College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China. zgdjjh@163.com.
Chemical Communications (Cambridge, England)
|November 22, 2023
Summary
Researchers developed novel covalent organic framework (COF) films using electron donors and acceptors. These materials exhibit strong nonlinear optical properties, offering a new pathway for optical material design.
Area of Science:
- Materials Science
- Chemistry
- Optics
Background:
- Covalent organic frameworks (COFs) are crystalline porous polymers with tunable properties.
- Developing advanced optical materials with strong nonlinearities is crucial for photonic applications.
Purpose of the Study:
- To synthesize and characterize novel COF films for optical applications.
- To investigate the structure-property relationships governing the nonlinear optical behavior of COFs.
Main Methods:
- Solvothermal synthesis of COF films on glass substrates using electron donor and acceptor precursors.
- Characterization of film properties, including nonlinear absorption coefficients.
Main Results:
- Two COF films were successfully synthesized using 1,3,5-triformylbenzene (TF) and 2,4,6-triformylphloroglucinol (TFP).
- The TFP-BD film demonstrated a significant nonlinear absorption coefficient of -3.01 × 105 cm GW-1.
- Electron aggregation via the donor-acceptor (D-A) effect, driven by polar carbonyl groups, modulated the electronic structure.
Conclusions:
- A novel approach for structural modulation of optical materials with strong nonlinearity was established.
- The synthesized COF films show promise for applications in nonlinear optics.
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