Multi-colour uranyl emission efficiently tuned by hexacyanidometallates within hybrid coordination frameworks

Area of Science:

• Materials Science
• Inorganic Chemistry
• Supramolecular Chemistry

Background:

• Coordination networks offer versatile structures for diverse applications.
• Uranyl ions (UO2^2+) are known for their unique photophysical properties.
• Hybrid organic-inorganic materials combine the advantages of both components.

Purpose of the Study:

• To synthesize and characterize novel hybrid organic-inorganic coordination networks.
• To investigate the luminescent properties of uranyl ions within these networks.
• To explore the tunability of emission color based on incorporated metal ions.

Main Methods:

• Hydrothermal synthesis of coordination networks.
• Single-crystal X-ray diffraction for structural determination.
• Luminescence spectroscopy to analyze emission properties.

Main Results:

• Successfully synthesized four unique coordination networks: three-dimensional and layered structures.
• Observed vibronically coupled charge transfer emission from uranyl ions.
• Demonstrated color tunability of emission from green to orange by varying the hexacyanidometallate (M = Co, Rh, Ir, Pt).

Conclusions:

• The reported hybrid coordination networks represent a novel class of functional materials.
• The tunable luminescence of uranyl ions in these networks opens avenues for optoelectronic devices.
• The strategic use of bridging ligands (cyanide, hydroxide, 4,4'-bpdo) is key to controlling network architecture and properties.