Open Metal-Organic Frameworks With Exceptional Pore Apertures for Inclusion of Large Molecules (Case No. 2012-216)

Summary

UCLA researchers have developed metal-organic frameworks (MOFs)/isoreticular MOFs (IRMOFs) that have exceptionally large pore apertures, enabling improved capacity and performance in gas storage, separation, and related applications.

Background

MOFs are porous crystalline materials made of metal nodes and organic linkers; large aperture pores are desirable for accommodating large molecules, improving mass transport, and increasing usable capacity. Existing MOFs sometimes suffer from limited pore size, pore blockage, or slow kinetics for molecules or gases to diffuse in/out. There is strong demand for frameworks that combine large pore size with structural stability, high surface area, and useful selectivity for gas storage, separation, filtration, or catalysis.

Innovation

This invention discloses MOFs or IRMOFs constructed by selecting specific organic linking moieties (linkers) and metals (e.g. Mg or Zn) that yield very large aperture MOFs. The MOFs use substituted or hetero-substituted linkers of defined structure to increase pore sizes without sacrificing structural integrity. These frameworks are characterized to have exceptional pore apertures, high surface area, and are usable for adsorption/separation of various gases or organic/inorganic molecules. The invention also includes methods for producing these MOFs, including the choice of linkers, metal centers, synthesis conditions, and potential functionalization.

Advantages

Exceptionally large pore apertures enable accommodating larger molecules or facilitating faster diffusion.
High surface areas increase capacity for gas adsorption or storage.
Structural stability thanks to well-chosen metal nodes and robust linkers.
Potential for high selectivity in gas separation or storage applications.
Flexibility in linker substitution allows tuning properties (pore size, functional groups, hydrophilicity/hydrophobicity etc.).
Useful for both organic and inorganic molecule adsorption, not limited to small gases.

Potential Applications

Gas storage (e.g. H₂, CH₄, CO₂) for energy or environmental applications.
Separation of large organic molecules or vapors (e.g. in chemical processing or purification).
Filtration or sieving of pollutants from water or air.
Catalysis supports with high accessibility of active sites.
Sensors that detect large molecules, volatile organics, or bio-molecules.

Publications

Large-Pore Apertures in a Series of Metal-Organic Frameworks. Hexiang Deng et al., Science 336, 1018 (2012); https://www.science.org/doi/10.1126/science.1220131