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Published on: October 5, 2019
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Linkage-Mediated Electronic Structure Modulation in Multicomponent Covalent Organic Frameworks for Dramatically
Yu Yan1, Yanming Zhao1, Xikai Chen1
1Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou, 450003, China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|May 15, 2024
Summary
Researchers engineered covalent organic frameworks (COFs) by modifying linkage chemistry to enhance photocatalytic hydrogen evolution. This strategy significantly boosted hydrogen production rates in pyrene-based COFs, offering a new pathway for efficient solar fuel generation.
Area of Science:
- Materials Science
- Photocatalysis
- Supramolecular Chemistry
Background:
- Covalent organic frameworks (COFs) are crucial for photocatalytic applications, but precise electronic structure modulation via linkage chemistry for efficient hydrogen evolution remains a significant challenge.
- Donor-acceptor (D-A) interactions within COFs play a key role in their optoelectronic properties and photocatalytic performance.
Purpose of the Study:
- To demonstrate a proof-of-concept for designing and synthesizing robust multicomponent pyrene-based COFs with engineered linkage chemistry for enhanced photocatalytic hydrogen evolution.
- To investigate the impact of controlled linkage modification on the electronic structure and photocatalytic activity of COFs.
Main Methods:
- Judicious design and synthesis of pyrene-based COFs through molecular engineering of linkage, incorporating abundant donor-acceptor (D-A) interactions.
- Controlled locking and conversion of linkage to continuously regulate COFs' electronic structures.
- Utilized diversified spectroscopy and theoretical calculations to analyze charge redistribution, π-conjugation, and D-A effects.
Main Results:
- Successfully synthesized robust pyrene-based COFs with tunable electronic structures via linkage engineering.
- Achieved a significant hydrogen evolution rate of 15.67 mmol g-1 h-1 with a protonated quinoline-linked COF decorated with a trifluoromethyl group (TT-PQCOF-CF3).
- Demonstrated that linkage modifications synergistically enhance charge redistribution, extend π-conjugation, and reinforce D-A effects, leading to boosted carrier separation and migration.
Conclusions:
- Linkage-mediated electronic structure modulation is a highly effective strategy for optimizing COF photocatalysts for hydrogen evolution.
- The developed TT-PQCOF-CF3 material shows significant promise for efficient solar fuel production.
- This study provides valuable guidance for designing high-performance COF photocatalysts by focusing on linkage chemistry.
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