Interpenetrated Metal-Organic Frameworks with ftw Topology and Versatile Functions

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Isoreticular expansion has yielded many porous zirconium-based metal-organic frameworks (Zr-MOFs).
• Interpenetrated Zr-MOFs with ftw topology are rare due to bulky linkers hindering network interpenetration.

Purpose of the Study:

• To report a new family of zirconium and lanthanide (Ln) MOFs with ftw topology.
• To investigate the interpenetration, stability, gas adsorption, and luminescence properties of these novel MOFs.

Main Methods:

• Synthesis of Zr and Ln MOFs using hexanuclear clusters and a spirobifluorene-center tetracarboxylate linker.
• Structural characterization to confirm ftw topology and double interpenetration.
• Gas adsorption studies (CO2) and luminescence measurements (UV-vis-NIR).

Main Results:

• A new family of isostructural, doubly interpenetrated Zr and Ln MOFs with ftw topology was successfully synthesized.
• The MOFs exhibit ultrahigh thermal and chemical stability, attributed to the linker's geometry.
• The interpenetrated Zr-MOF shows high porosity and excellent CO2 storage performance due to a strong CO2 binding environment.
• The MOFs display characteristic luminescence and efficient two-photon-excited photoluminescence.

Conclusions:

• The spirobifluorene-center linker facilitates unusual double interpenetration in Zr-MOFs with ftw topology.
• These stable, porous MOFs are promising for CO2 capture and advanced optical applications.
• The interpenetrated structure enhances luminescence properties and CO2 binding.