Elucidating descriptors for crystallinity control in halogenated covalent organic frameworks

Abstract

Covalent organic frameworks (COFs) represent an extensively studied material featuring crystalline scaffolds drawing direct inspiration from dynamic covalent chemistry. Fluorinated COFs (F-COFs) exhibit unique properties, promising applications, and enhanced crystallinity and porosity compared to their non-fluorinated counterparts. However, specific descriptors for precisely controlling crystallinity through bottom-up synthesis remain lacking. In this work, systematic studies have been performed to dig out the critical factors governing the crystallinity and porosity of diverse halogenated COF scaffolds functionalized by F, Cl, and Br-involved moieties. By combining experimental COF construction and characterization with first principles simulations, it is demonstrated that the imine bond formation energy plays a pivotal role in determining the quality of halogenated COFs derived from aromatic aldehyde and amine monomers employed herein, with the optimal reaction enthalpies lying in the range of −1.27 to −1.54 kcal mol−1, using mesitylene/dioxane as the solvent and acetic acid as the catalyst. The precise correlation between crystallinity and bond formation energy established through these systematic synthesis–simulation studies offers a novel guiding principle for constructing highly crystalline COF scaffolds.

Graphical abstract: Elucidating descriptors for crystallinity control in halogenated covalent organic frameworks

Supplementary files

Article information

Article type
Communication
Submitted
04 Jun 2025
Accepted
10 Jul 2025
First published
11 Jul 2025

CrystEngComm, 2025, Advance Article

Elucidating descriptors for crystallinity control in halogenated covalent organic frameworks

E. Li, X. Suo, L. Qiu, J. Fan, S. Wang, D. Jiang, I. Popovs, Z. Yang and S. Dai, CrystEngComm, 2025, Advance Article , DOI: 10.1039/D5CE00578G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements