Metal-organic frameworks based on flexible ligands (FL-MOFs): structures and applications

Area of Science:

• Materials Science
• Chemistry
• Crystallography

Background:

• Metal-organic frameworks (MOFs), or coordination polymers (CPs), are crystalline materials formed from metal ions and organic ligands.
• MOFs based on rigid ligands (RL-MOFs) are widely studied, while those using flexible ligands (FL-MOFs) are less explored.
• Flexible ligands introduce unique structural possibilities and material properties despite reduced design control.

Purpose of the Study:

• To review the design principles and structural diversity of flexible ligand-based metal-organic frameworks (FL-MOFs).
• To briefly outline homochiral FL-MOFs and dynamic frameworks.
• To provide an overview of FL-MOF applications.

Main Methods:

• Literature review focusing on FL-MOF design and synthesis.
• Analysis of structural characteristics and properties of FL-MOFs.
• Compilation of reported applications of FL-MOFs.

Main Results:

• Flexible ligands enable novel crystalline framework materials with desirable attributes.
• Significant structural diversity exists within FL-MOFs.
• FL-MOFs show promise in gas adsorption, heterogeneous catalysis, and proton conduction.

Conclusions:

• FL-MOFs represent an underexplored but promising class of materials.
• The use of flexible ligands opens new avenues for MOF design and application.
• Further research into FL-MOFs is warranted for advanced material development.