Combining coordination and chelation moieties to engineer a new linker for lanthanide coordination chemistry

Area of Science:

• Materials Science
• Inorganic Chemistry
• Coordination Chemistry

Background:

• Organic linkers are essential for designing lanthanide coordination polymers (Ln-CPs).
• The ligand 6-oxo-1,6-dihydro-2,5-pyridinedicarboxylic acid (2,5-H3PODC) combines features of terephthalic acid and pyridinone groups.

Purpose of the Study:

• To synthesize and characterize new lanthanide coordination polymers using the 2,5-H3PODC ligand.
• To investigate the structural diversity, thermal stability, and photoluminescent properties of the resulting Ln-CPs.

Main Methods:

• Solvothermal synthesis of six lanthanide coordination polymers.
• Structural characterization using single-crystal and powder X-ray diffraction.
• Thermal analysis via thermogravimetric analysis (TGA).
• Photoluminescence spectroscopy for Eu(III)-containing compound.

Main Results:

• Two types of 2D ladder-like networks (type 1 and type 2) were formed with varying lanthanide ions and co-ligands (oxalic acid).
• Structural characterization confirmed the bridging roles of 2,5-H3PODC derivatives and oxalic acid.
• TGA revealed distinct decomposition patterns for the two types of Ln-CPs.
• Eu(III) compound (3) exhibited efficient ligand-based sensitization and characteristic luminescence.

Conclusions:

• The 2,5-H3PODC ligand is effective in constructing diverse lanthanide coordination polymers.
• The synthesized Ln-CPs display unique structural topologies and tunable physicochemical properties.
• These findings contribute to the development of new materials for potential applications in luminescence and catalysis.