Advancement of Actinide Metal-Organic Framework Chemistry via Synthesis of Pu-UiO-66

Area of Science:

• Materials Science
• Radiochemistry
• Inorganic Chemistry

Background:

• The UiO-66 series of metal-organic frameworks (MOFs) is known for its stability and porosity, with nodes incorporating various metals.
• Previous research has included transition metals, lanthanides, and early actinides in UiO-66 structures.
• Plutonium, a late actinide, has not yet been incorporated into the UiO-66 framework.

Purpose of the Study:

• To report the synthesis and characterization of the first plutonium-based metal-organic framework (Pu-UiO-66).
• To investigate the thermal stability, porosity, and structural properties of Pu-UiO-66.
• To explore the coordination chemistry of plutonium within a MOF structure and understand synthesis competition.

Main Methods:

• Experimental synthesis and characterization of Pu-UiO-66.
• Determination of thermal stability and porosity through experimental measurements.
• Multifaceted computational methods including density functional theory (DFT) for electronic structure, defect analysis, and spectroscopic signature elucidation.

Main Results:

• Successful synthesis and characterization of the first plutonium metal-organic framework, Pu-UiO-66.
• Experimental determination of thermal stability and porosity.
• Computational analysis corroborated experimental findings, revealed framework defects, and elucidated electronic structure.
• Observation of a plutonium chain side product, indicating competition between modulator and linker during synthesis.

Conclusions:

• The synthesis of Pu-UiO-66 demonstrates controlled plutonium(IV) coordination under challenging hydrolysis conditions.
• This work extends the isostructural trends observed in the UiO-66 series to include plutonium.
• Pu-UiO-66 serves as a foundational material for future research in plutonium-based metal-organic frameworks.