Multivalent Ion-Conducting Metal- and Covalent- Organic Frameworks

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) possess tunable nanoporous architectures.
• Incorporating ionic groups into these frameworks creates additional ion hopping sites.
• These materials are promising candidates for ion conductors in multivalent-ion batteries.

Purpose of the Study:

• To review the structures and ion transport mechanisms in MOFs and COFs for multivalent ion conduction.
• To outline design principles for enhancing ionic conductivity in these materials.
• To explore the applications of MOFs/COFs in multivalent batteries and propose future research directions.

Main Methods:

• Examination of framework flexibility and functionalization effects on ion transport.
• Comparison of various synthetic methods (e.g., grinding, milling, reflux, hydrothermal, interfacial) for MOF/COF preparation.
• Analysis of structural design principles for maximizing ionic conductivity.

Main Results:

• Framework flexibility and functionalization reduce activation energies for bulky multivalent cations.
• Incorporation of ionic groups is key to maximizing ionic conductivity.
• MOFs/COFs demonstrate potential as solid electrolytes, membranes, and interfacial coatings.

Conclusions:

• MOFs and COFs offer tunable pathways for efficient multivalent ion transport.
• Strategic design and synthesis are crucial for developing practical MOF/COF conductors.
• These materials hold significant potential for advancing multivalent-ion energy storage systems.