A Multifunctional Zn(II) Metallohydrogel for Anionic Dye Adsorption and Catalytic CO₂ Fixation

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Green Chemistry

Background:

• Development of advanced functional materials is crucial for addressing environmental challenges.
• Metallohydrogels offer unique properties due to the combination of metal ions and supramolecular networks.
• Amino-acid-based gelators provide a sustainable and versatile platform for material synthesis.

Purpose of the Study:

• To synthesize and characterize a multiresponsive Zn(II) metallohydrogel using a novel amino-acid-based gelator.
• To investigate the self-healing, adsorption, and catalytic properties of the synthesized metallohydrogel.
• To explore the potential applications of the metallohydrogel in dye removal and carbon dioxide fixation.

Main Methods:

• Synthesis of the amino-acid-based ligand (H3L) and its Zn(II) metallohydrogel.
• Characterization using techniques including FTIR, NMR, HRMS, rheology, MALDI-TOF, FESEM, TEM, AFM, BET, PXRD, and TGA.
• Evaluation of adsorption capacity for Congo red dye and catalytic activity for CO2 fixation with epoxides.

Main Results:

• The Zn(II) metallohydrogel exhibited self-healing and self-sustaining characteristics.
• The xerogel (dried form) showed significant Congo red adsorption (128.2 mg/g), following Langmuir isotherm and pseudo-second-order kinetics.
• The xerogel demonstrated efficient heterogeneous catalysis for the fixation of carbon dioxide with epoxides under solvent-free conditions.

Conclusions:

• A multifunctional Zn(II) metallohydrogel was successfully synthesized.
• The material possesses promising capabilities for dye adsorption and catalytic applications, highlighting its utility in environmental remediation and sustainable chemical processes.