Continuous structure modification of metal-organic framework glasses via halide salts

Area of Science:

• Materials Science
• Chemistry
• Solid-State Chemistry

Background:

• Metal-organic frameworks (MOFs) melting and glass formation are crucial for bulk material processing.
• Limited MOF crystals form glasses, and strategies for tuning their properties are underdeveloped.

Purpose of the Study:

• To address challenges in MOF glass formation and property tuning.
• To develop a strategy for co-melting zeolitic imidazole frameworks (ZIFs) with halide salts.

Main Methods:

• Co-melting of ZIFs with heterocycle-based halide salts.
• Experimental and computational analyses to understand salt modification effects.
• Tuning the fraction of bridging to non-bridging imidazolate linkers.

Main Results:

• Halide salts act as chemical modifiers, enabling ZIF-8 melting without decomposition.
• Salts depolymerize ZIFs, allowing continuous tuning of linker fractions.
• Tunable thermal and mechanical properties of the resulting MOF glasses were achieved.

Conclusions:

• The co-melting strategy diversifies MOF glass chemistry.
• This approach enables tunable structures and properties for glass-forming MOFs.
• The method increases the number of MOFs capable of forming glasses with enhanced functionalities.