The Effect on the Luminescent Properties in Lanthanide-Titanium OXO Clusters

Area of Science:

• Inorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Lanthanide-titanium oxo clusters (LTOCs) are advanced materials with potential applications in luminescence and sensing.
• Understanding the structure-property relationships of LTOCs is crucial for designing materials with tailored functionalities.

Purpose of the Study:

• To synthesize and structurally characterize two new LTOCs with distinct architectures.
• To investigate the luminescence properties of these LTOCs and their response to fluoride ion (F-) addition.
• To elucidate the factors influencing luminescence efficiency and lifetime in these complexes.

Main Methods:

• Solvothermal synthesis using lanthanide (Europium), titanium precursors, and a 4-tert-butylbenzoate ligand.
• Single-crystal X-ray diffraction for detailed structural analysis of the LTOCs.
• Luminescence spectroscopy (lifetime and quantum yield measurements) to evaluate photophysical properties.

Main Results:

• Two LTOCs, [Eu3Ti3(μ3-O)2(μ3-OH)(CH3O)2(Ac)2(CH3OH)(tbba)12]·CH3OH (1) and [Eu6Ti8(μ3-O)13(μ2-OH)(μ3-OCH3)2(μ2-OCH3)2(H2O)(CH3OH)2(tbba)19]·Htbba·10H2O (2), were successfully synthesized and structurally elucidated.
• Cluster 1 exhibited a luminescence lifetime of 1212 μs and a quantum yield of 69.6%.
• Upon addition of F-, cluster 1 showed a 1.3-fold increase in quantum yield and an increase in lifetime to 1.4 ms, while cluster 2 showed no significant enhancement.

Conclusions:

• The structural differences, particularly the reduced presence of non-radiative O-H vibration groups in cluster 1 compared to cluster 2, significantly impact luminescence performance.
• Cluster 1 demonstrates potential as a luminescent material, with its properties being tunable through external stimuli like F- ions.