Catalytic CO₂ Fixation over a Robust Lactam-Functionalized Cu(II) Metal Organic Framework

Area of Science:

• Materials Science
• Catalysis
• Green Chemistry

Background:

• Metal-organic frameworks (MOFs) offer tunable porous structures for catalysis.
• Efficient CO2 conversion is crucial for sustainable chemistry.
• Lactam functionalization can enhance MOF properties and catalytic activity.

Purpose of the Study:

• To synthesize and characterize a novel lactam-functionalized Cu-MOF.
• To investigate the catalytic performance of the activated Cu-MOF' for CO2 conversion.
• To explore the recyclability and reusability of the Cu-MOF' catalyst.

Main Methods:

• Synthesis of Cu-MOF using a rigid lactam-functionalized ditopic ligand (H2L) under slow evaporation.
• Single crystal X-ray diffraction for structural analysis.
• Activation of Cu-MOF at 150 °C under vacuum to generate Cu-MOF' with unsaturated Cu(II) sites.
• Solvent-free heterogeneous catalytic conversion of CO2 to cyclic carbonates using Cu-MOF'.

Main Results:

• A 3D porous Cu-MOF with 1D channels decorated with lactam groups was successfully synthesized.
• Activation yielded a solvent-free Cu-MOF' with Lewis acidic Cu(II) sites.
• Cu-MOF' demonstrated efficient, solvent-free catalytic conversion of CO2 to cyclic carbonates under mild conditions.
• The Cu-MOF' catalyst exhibited excellent recyclability over several cycles.

Conclusions:

• The synthesized lactam-functionalized Cu-MOF' is an effective catalyst for CO2 conversion.
• The material's porous structure and unsaturated Cu(II) sites are key to its catalytic activity.
• The solvent-free and recyclable nature of Cu-MOF' highlights its potential for sustainable chemical processes.