Covalent Organic Frameworks for Water Sorption: The Importance of Framework Physical Stability
Abstract Covalent organic frameworks (COFs) have garnered growing interest as water‐sorption adsorbents. While the chemical stability of most COFs in liquid‐phase water is well‐established, there are limited studies on their framework physical stability in water vapor. This refers to maintaining the ordered structure of COFs without disrupting their chemical bonds, a factor that significantly influences water sorption. Here, the water‐vapor stability of three distinct 2D COFs with various pore sizes is examined. Microporous COFs exhibit superior stability compared to mesoporous COFs (with pore sizes ranging from 2.2 to 3.8 nm), although their water‐uptake capacity shows a decreasing trend. Mesoporous keto‐enamine‐linked COFs with the intralayer hydrogen bonds between carbonyl oxygen and secondary amine hydrogen atoms exhibited markedly improved water‐vapor stability compared to imine‐linked COFs, which is further confirmed by molecular dynamics simulations, density functional theory calculations, and the extended water adsorption‐desorption cycling test (200 cycles). Finally, a COF‐coated heat exchanger is fabricated to demonstrate air dehumidification at a device level.
Authors
- Wei Juan Zhao (ORCID: https://orcid.org/0000-0003-0265-2590)
- Mounib Bahri (ORCID: https://orcid.org/0000-0002-8336-9158)
- K.J. Chua (ORCID: https://orcid.org/0000-0001-9293-7471)
- Nigel D. Browning (ORCID: https://orcid.org/0000-0003-0491-251X)
- He Li (ORCID: https://orcid.org/0000-0003-0830-0844)
- Weidong Chen (ORCID: https://orcid.org/0000-0001-8757-0679)
- Ting Chen (ORCID: https://orcid.org/0000-0002-6616-0512)
- Boyu Li (ORCID: https://orcid.org/0000-0002-7648-3745)
- Qiang Zhu (ORCID: https://orcid.org/0000-0002-9892-0344)
- Zekun Wang (ORCID: https://orcid.org/0000-0001-5175-4118)
- Chengjun Kang (ORCID: https://orcid.org/0000-0003-0208-2954)
- Dan Zhao (ORCID: https://orcid.org/0000-0002-4427-2150)
- Kexin Yu (ORCID: https://orcid.org/0000-0001-6261-7485)
- Bui Duc Thuan
Institutions
- University of Liverpool (GB)
- National University of Singapore (SG)
- Leverhulme Trust (GB)
- Suzhou Research Institute (CN)
Publication Details
- Journal
- Advanced Functional Materials
- Published
- 2025-09-18
- DOI
- https://doi.org/10.1002/adfm.202514901
- Citations
- 1
- Primary Topic
- Covalent Organic Framework Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.52
Funders
- National Research Foundation
- Agency for Science, Technology and Research
- National University of Singapore
- National Research Foundation Singapore
- Energy Market Authority of Singapore
- Government of Jiangsu Province
- Ministry of Education, India
- Science and Technology Support Program of Jiangsu Province