Mixed-linker approach employing a flexible monomer for constructing highly crystalline multiple-component covalent
Yogesh Kumar1, Sandeep Gupta1, Shyamapada Nandi2
1Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, 247667, India. rpandey@cy.iitr.ac.in.
Materials Horizons
|September 2, 2025
Summary
Flexible linkers enable the synthesis of diverse covalent organic frameworks (COFs). Multicomponent COFs with enhanced functionalities show improved photocatalytic activity for converting aryl phenylboronic acid to phenol.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Covalent organic frameworks (COFs) are versatile materials for catalysis, gas storage, and energy applications.
- Traditional two-component synthesis limits COF structural diversity and achievable properties.
- Multicomponent strategies offer greater flexibility but underexplore flexible linkers.
Purpose of the Study:
- To investigate the use of flexible linkers in multicomponent COF synthesis.
- To synthesize and characterize novel COFs with varying component numbers.
- To evaluate the photocatalytic performance of synthesized COFs.
Main Methods:
- Employed a flexible amine linker combined with four distinct aldehyde linkers in various combinations.
- Synthesized fifteen crystalline COFs, including two-, three-, four-, and five-component frameworks.
- Conducted comparative photocatalytic studies using aryl phenylboronic acid conversion.
Main Results:
- Successfully synthesized fifteen diverse, highly crystalline COFs using flexible linkers.
- Five-component COFs exhibited higher surface area and enhanced visible-light absorption compared to two-component COFs.
- Increased structural functionalities correlated with enhanced photocatalytic activity.
Conclusions:
- Flexible linkers are crucial for expanding the structural diversity of COFs.
- Multicomponent COFs with tailored functionalities demonstrate superior photocatalytic performance.
- This approach opens new avenues for designing advanced COF materials for various applications.
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