Three-Dimensional Covalent Organic Frameworks with lil Topology
Xinyu Wu1, Hanwen Wang1, Ning Huang1
1State Key Laboratory of Silicon and Advanced Semiconductor Materials, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China.
Journal of the American Chemical Society
|February 8, 2025
Summary
Researchers developed novel 3D covalent organic frameworks (COFs) with a unique lil topological structure. These new COFs exhibit a record-high dielectric constant, making them promising for advanced capacitor applications.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Covalent Organic Frameworks (COFs) offer tunable structures and properties.
- Developing crystalline 3D COFs with novel topologies remains a significant challenge.
Purpose of the Study:
- To design and synthesize new 3D COFs with a specific lil topological structure.
- To investigate the dielectric properties of these novel COFs for potential applications.
Main Methods:
- Assembly of 3D COFs using D4h- and C2h-symmetric building blocks.
- Crystallographic analysis to determine the Imma space group and network topology.
- Measurement of dielectric constant and loss at high frequencies (>1 kHz).
Main Results:
- Successful development of 3D COFs with the lil topological structure.
- Formation of a noninterpenetrated network with D4h and C2h units.
- Achieved a record-high dielectric constant of 63 with low dielectric loss.
Conclusions:
- The study provides a blueprint for designing 3D lil-net COFs.
- The synthesized COFs are promising materials for high-energy-density and pulsed capacitors.
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