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Abstract Emissive covalent organic frameworks (COFs) have recently emerged as next‐generation porous materials with attractive properties such as tunable topology, porosity, and inherent photoluminescence. Among the different types of COFs, substoichiometric frameworks (so‐called Type III COFs) are especially attractive due to the possibility of not only generating unusual topology and complex pore architectures but also facilitating the introduction of well‐defined functional groups at precise locations for desired functions. Herein, the first example of a highly emissive (PLQY 6.8%) substoichiometric 2D‐COF (COF‐SMU‐1) featuring free uncondensed aldehyde groups is reported. In particular,COF‐SMU‐1features a dual‐pore architecture with an overallbexnet topology, tunable emission in various organic solvents, and distinct colorimetric changes in the presence of water. To gain further insights into its photoluminescence properties, the charge transfer, excimer emission, and excited state exciton dynamics ofCOF‐SMU‐1are investigated using femtosecond transient absorption spectroscopy in different organic solvents. Additionally, highly enhanced atmospheric water‐harvesting properties ofCOF‐SMU‐1are revealed using FT‐IR and water sorption studies.The findings will not only lead to in‐depth understanding of structure–property relationships in emissive COFs but also open new opportunities for designing COFs for potential applications in solid‐state lighting and water harvesting.
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Opportunities of Covalent Organic Frameworks for Advanced Applications
Abstract Covalent organic frameworks (COFs) are an emerging class of functional nanostructures with intriguing properties, due to their unprecedented combination of high crystallinity, tunable pore size, large surface area, and unique molecular architecture. The range of properties characterized in COFs has rapidly expanded to include those of interest for numerous applications ranging from energy to environment. Here, a background overview is provided, consisting of a brief introduction of porous materials and the design feature of COFs. Then, recent advancements of COFs as a designer platform for a plethora of applications are emphasized together with discussions about the strategies and principles involved. Finally, challenges remaining for this type material for real applications are outlined.
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- Award ID(s):
- 1706025
- PAR ID:
- 10462852
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 6
- Issue:
- 2
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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