Three-Component Donor-π-Acceptor Covalent-Organic Frameworks for Boosting Photocatalytic Hydrogen Evolution

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Two-dimensional covalent-organic frameworks (2D COFs) show promise for solar-to-hydrogen conversion.
• Current limitations include inefficient solar energy capture and rapid charge recombination, hindering performance.

Purpose of the Study:

• To develop novel 2D COFs with improved photocatalytic activity for hydrogen production.
• To investigate the structure-property relationships governing enhanced performance.

Main Methods:

• Synthesized two photoactive three-component donor-π-acceptor (TCDA) materials using a multicomponent strategy.
• Incorporated electron-deficient triazine and electron-rich benzotrithiophene moieties via sp2 carbon and imine linkages.
• Employed diversified spectroscopy and theoretical prediction to analyze properties.

Main Results:

• The novel TCDA-COFs exhibit tunable photophysical properties and enhanced photocatalytic activity.
• The sp2 carbon-linked TCDA-COF achieved a hydrogen evolution rate of 70.8 ± 1.9 mmol g-1 h-1 with Pt co-catalyst.
• Full π-conjugated linkages improved visible-light harvesting and charge transfer/separation efficiency.

Conclusions:

• The developed TCDA-COFs offer a promising platform for efficient solar hydrogen production.
• The findings highlight the importance of π-conjugated linkages for optimizing photocatalytic performance.
• These materials demonstrate excellent reusability and potential for practical applications.