Semiconductive Amine-Functionalized Co(II)-MOF for Visible-Light-Driven Hydrogen Evolution and CO₂ Reduction

Area of Science:

• Materials Science
• Catalysis
• Photochemistry

Background:

• Metal-organic frameworks (MOFs) offer tunable properties for catalytic applications.
• Cobalt-based MOFs are explored for their potential in energy conversion reactions.
• Photocatalytic hydrogen evolution and CO2 reduction are crucial for sustainable energy solutions.

Purpose of the Study:

• To synthesize and characterize a novel trinuclear cobalt metal-organic framework (Co-MOF).
• To investigate the Co-MOF's performance in photocatalytic hydrogen evolution.
• To evaluate the Co-MOF's efficacy in photocatalytic CO2 reduction without additional cocatalysts.

Main Methods:

• One-pot solvothermal synthesis of the Co-MOF.
• Band gap determination using the Kubelka-Munk method.
• Photocatalytic experiments for H2 evolution and CO2 reduction.

Main Results:

• The synthesized Co-MOF, [Co3(HL)2·4DMF·4H2O], possesses a band gap of 2.95 eV.
• Optimized H2 evolution reached 1102 μmol/(g h) with specific catalyst preparation and reaction conditions.
• CO2 reduction achieved an activity of 456.0 μmol/(g h) using the Co-MOF with an amine functional group for light absorption.

Conclusions:

• The novel trinuclear Co-MOF demonstrates promising photocatalytic activity for both H2 evolution and CO2 reduction.
• The study highlights the importance of photosensitizer, solvent, and catalyst preparation for H2 evolution efficiency.
• The integrated design of the Co-MOF enables CO2 reduction without external cocatalysts, showcasing its potential in sustainable chemistry.