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DOE OSTI · 2369574

Highly Flexible Dielectric Films from Solution Processable Covalent Organic Frameworks**

Senarathna, Milinda C.·Li, He·Perera, Sachini D.·Torres‐Correas, Jose·Diwakara, Shashini D.·Boardman, Samuel R.·Al‐Kharji, Noora M.·Liu, Yi·Smaldone, Ronald A.
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Abstract

Covalent organic frameworks (COFs) are known to be a promising class of materials for a wide range of applications, yet their poor solution processability limits their utility in many areas. Here we report a pore engineering method using hydrophilic side chains to improve the processability of hydrazone and β-ketoenamine-linked COFs and the production of flexible, crystalline films. Further, mechanical measurements of the free-standing COF films of COF-PEO-3 (hydrazone-linked) and TFP-PEO-3 (β-ketoenamine-linked), revealed a Young's modulus of 391.7 MPa and 1034.7 MPa, respectively. The solubility and excellent mechanical properties enabled the use of these COFs in dielectric devices. Specifically, the TFP-PEO-3 film-based dielectric capacitors display simultaneously high dielectric constant and breakdown strength, resulting in a discharged energy density of 11.22 J cm -3 . This work offers a general approach for producing solution processable COFs and mechanically flexible COF-based films, which hold great potential for use in energy storage and flexible electronics applications.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYcovalent organic frameworksdielectricsdynamic covalent chemistryfilm fabricationmechanical characterization

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Senarathna, Milinda C., Li, He, Perera, Sachini D., Torres‐Correas, Jose, Diwakara, Shashini D., Boardman, Samuel R., Al‐Kharji, Noora M., Liu, Yi, Smaldone, Ronald A.. 2023-10-18. Highly Flexible Dielectric Films from Solution Processable Covalent Organic Frameworks**. https://doi.org/10.1002/anie.202312617

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