MIL-101(Fe)-derived porous amorphous materials for efficient Congo red adsorption.

Area of Science:

• Materials Science
• Environmental Chemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) like MIL-101(Fe) are effective adsorbents.
• Amorphization can alter material properties, potentially improving performance.
• Congo red (CR) is a common pollutant requiring efficient removal methods.

Purpose of the Study:

• To prepare novel porous amorphous materials derived from MIL-101(Fe).
• To investigate the adsorption performance of these materials for Congo red.
• To understand the factors influencing adsorption and the underlying mechanisms.

Main Methods:

• Synthesis of porous amorphous materials using MIL-101(Fe) and 2-methylimidazole (2-MelM).
• Characterization via SEM, XRD, BET, FT-IR, and XPS.
• Adsorption experiments evaluating dye concentration, pH, temperature, and time effects.

Main Results:

• Amorphization significantly enhanced CR adsorption capacity compared to pristine MIL-101(Fe).
• Optimal conditions yielded a maximum adsorption capacity of 7078 mg g⁻¹.
• Langmuir model indicated monolayer adsorption with a saturated capacity of 7095 mg g⁻¹.
• Materials exhibited high stability and reusability.

Conclusions:

• Amorphization of MIL-101(Fe) is an effective strategy to boost Congo red adsorption.
• The developed materials show superior performance and stability for dye removal.
• Hydrogen bonding, electrostatic, and π-π interactions are key to the adsorption mechanism.