Flexible metal-organic frameworks: Frontiers in dynamic pore engineering for adsorptive separation

Area of Science:

• Materials Science
• Chemical Engineering
• Nanotechnology

Background:

• Flexible metal-organic frameworks (FMOFs) present a low-energy alternative to traditional separation processes.
• Their practical application is hindered by structural instability and co-adsorption issues due to excessive flexibility.

Purpose of the Study:

• To review pioneering strategies for overcoming FMOF limitations.
• To emphasize dynamic pore engineering techniques for modulating flexibility and selectivity.

Main Methods:

• Pore functionalization and controlled interpenetration for dynamic pore engineering.
• Analysis of FMOF efficacy in gas and liquid organic mixture separations.
• Investigation of stimuli-responsive mechanisms using advanced characterization and theoretical modeling.

Main Results:

• Dynamic pore engineering effectively modulates FMOF flexibility while maintaining high selectivity.
• FMOFs demonstrate significant efficacy in gas separations and challenging liquid mixtures like hexane and xylene isomers.
• External stimuli and guest molecules synergistically influence separation mechanisms.

Conclusions:

• Addressing challenges in green synthesis, shaping, and long-term stability is crucial for industrial FMOF deployment.
• Advanced characterization and modeling are vital for understanding dynamic phase transitions.
• This review serves as a blueprint for developing next-generation intelligent separation materials.