Visible-Light Driven Oxygen Evolution From Water With a Donor-Acceptor Covalent Organic Framework Photocatalyst

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• The oxygen evolution reaction (OER) is a critical bottleneck in photocatalytic water splitting for solar fuel generation.
• Developing efficient and stable catalysts is essential to overcome OER kinetics.

Purpose of the Study:

• To design and synthesize a novel donor-acceptor covalent organic framework (COF) for enhanced photocatalytic water splitting.
• To integrate atomically dispersed cobalt sites onto the COF for improved light harvesting and catalytic activity.

Main Methods:

• Synthesis of a donor-acceptor COF using pyrylium and trihydroxybenzene monomers.
• Post-synthetic modification to anchor atomically dispersed Co²⁺ sites, creating Co-TTN-COF.
• Evaluation of photocatalytic activity for water oxidation under visible-light irradiation.

Main Results:

• The synthesized Co-TTN-COF exhibited extended light absorption into the red region of the visible spectrum.
• The catalyst achieved a high average oxygen evolution rate of 249 μmol h⁻¹ g⁻¹.
• The integrated system demonstrated efficient light-harvesting and catalytic functions for water oxidation.

Conclusions:

• The developed Co-TTN-COF represents a promising strategy for efficient and stable photocatalytic water splitting.
• This approach offers a new pathway for designing integrated COF-based photocatalytic systems for solar fuel production.