Metal-organic framework patterns and membranes with heterogeneous pores for flow-assisted switchable separations

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Porous metal-organic frameworks (MOFs) are widely used in gas storage, separations, and catalysis.
• A key challenge is creating larger pores within MOFs to complement existing micropores for new functionalities.
• Existing MOF structures often lack the necessary pore hierarchy for complex molecular separations.

Purpose of the Study:

• To develop a method for creating heterogeneous pores within MOF materials.
• To demonstrate the formation of these pores in various MOF forms (particles, patterns, membranes).
• To explore the application of these heterogeneous pores in selective separations.

Main Methods:

• Utilized a silver-catalyzed decarboxylation process for discriminate etching.
• Applied the method to stable MOF structures without altering their fundamental framework.
• Fabricated MOF membranes and tested their separation capabilities.

Main Results:

• Successfully created heterogeneous pores in MOF particles, patterns, and membranes.
• Demonstrated that the etching process preserves the original MOF structure.
• Developed a MOF membrane with pH-responsive switchable selectivity for protein separation.

Conclusions:

• The silver-catalyzed decarboxylation method effectively introduces heterogeneous pores into MOFs.
• Heterogeneous pores enable advanced separation of similarly sized molecules, such as proteins.
• This technique holds promise for applications in molecular separation, energy, and electronic devices.