A solvent-responsive terbium-organic framework for photocatalytic CO₂ reduction.

Area of Science:

• Materials Chemistry
• Photocatalysis
• Coordination Chemistry

Background:

• Metal-organic frameworks (MOFs) are promising materials for catalysis due to their tunable structures and high surface areas.
• Efficient CO2 reduction is crucial for mitigating climate change and developing sustainable energy solutions.
• Developing novel MOFs with enhanced photocatalytic activity and selectivity is an active area of research.

Purpose of the Study:

• To synthesize and characterize a new terbium-based MOF (Tb-MOF) with a unique topological structure.
• To investigate the photocatalytic activity of the synthesized MOF for CO2 reduction.
• To explore the influence of solvent on the MOF's photocatalytic performance.

Main Methods:

• Solvothermal synthesis of the Tb-MOF, denoted as AQNU-4.
• Structural characterization using X-ray diffraction to determine the topology and building units.
• Photocatalytic evaluation of CO2 reduction using gas chromatography to quantify CO production.
• Systematic screening of various solvents to assess solvent-dependent catalytic activity.

Main Results:

• A novel Tb-MOF, AQNU-4, with a 5,5,6-c 3-nodal net and an unusual topological type was successfully synthesized.
• AQNU-4 exhibits efficient light harvesting and electron-hole separation, making it an effective photocatalyst for CO2 reduction.
• The photocatalytic performance of AQNU-4 is significantly influenced by the reaction solvent, with cyclohexanone showing the highest CO2 to CO conversion (138.65 μmol g⁻¹ h⁻¹).

Conclusions:

• AQNU-4 is a promising solvent-responsive MOF material for efficient CO2 reduction.
• The solvent dependence highlights the importance of solvent engineering in optimizing MOF-based photocatalytic systems.
• This study contributes to the design of advanced MOFs for sustainable chemical transformations.