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Updated: Jun 13, 2026
08:42
Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
Published on: July 10, 2017
Topology-Driven Node-Linker Coupling Enables Exceptional Thermal and Mechanical Performance in Covalent Organic
Achyut Subedi1, Patrick E Hopkins2,3,4, Ashutosh Giri1
1Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, United States.
ACS Nano
|June 12, 2026
Summary
Covalent organic frameworks (COFs) achieve high thermal and mechanical performance in lightweight materials by controlling topology. This design principle enables optimized phonon transport and rigidity, outperforming traditional porous solids.
Area of Science:
- Materials Science
- Computational Chemistry
- Nanotechnology
Background:
- Lightweight materials with high thermal and mechanical performance are crucial for advanced applications.
- Achieving this combination in porous solids is challenging due to inherent trade-offs between porosity, stiffness, and heat transport.
- Covalent organic frameworks (COFs) offer a potential solution through tunable structures.
Purpose of the Study:
- To investigate how topology influences thermal transport and elastic properties in three-dimensional COFs.
- To demonstrate that COF topology can overcome limitations in achieving simultaneous high thermal and mechanical performance.
- To establish a design principle for creating advanced lightweight thermomechanical materials.
Main Methods:
- Employed a computational framework integrating density functional tight binding and machine-learned interatomic potentials.
- Systematically studied thermal conductivity and elastic behavior in COFs with varied topologies but similar chemistry and density.
- Utilized spectral and heat-flux decomposition analyses to understand phonon transport mechanisms.
Main Results:
- Framework topology alone was shown to tune thermal conductivity by over an order of magnitude and elastic modulus by a factor of 10.
- Optimized COFs achieved room-temperature thermal conductivities >10 W m⁻¹ K⁻¹ and Young's moduli ~160 GPa.
- Cooperative node-linker vibrational coupling in COFs led to long phonon lifetimes and mean free paths, comparable to inorganic crystals.
Conclusions:
- Node-linker topology is a powerful design principle for simultaneously optimizing thermal and mechanical properties in nanoporous materials.
- COFs can overcome the typical trade-offs seen in porous solids, enabling high performance in lightweight structures.
- These findings provide a roadmap for designing next-generation lightweight thermomechanical materials.
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