Synthesis, structures and properties of six lanthanide complexes based on a 2-(2-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline ligand

Structural Features of Eu3+ and Tb3+-Bipyridinedicarboxamide Complexes

Photoluminescent lanthanide complexes of Eu³⁺ and Tb³⁺ as central atoms and N⁶,N⁶'-diisopropyl-[2,2'-bipyridine]-6,6'-dicarboxamide as ligand were synthesized. The structure of these complexes was established by single-crystal X-ray diffraction, mass spectrometry, ¹H and ¹³C nuclear magnetic resonance, ultraviolet-visible, infrared spectroscopy, and thermogravimetry. Bipyridinic ligands provide formation of coordinatively saturated complexes of lanthanide ions and strong photoluminescence (PL). The Eu³⁺- and Tb³⁺-complexes exhibit PL emission in the red and green regions observed at a 340 nm excitation. The quantum yield for the complexes was revealed to be 36.5 and 12.6% for Tb³⁺- and Eu³⁺-complexes, respectively. These lanthanide compounds could be employed as photoluminescent solid-state compounds and as emitting fillers in polymer (for example, polyethylene glycol) photoluminescent materials.

Encapsulation-Led Adsorption of Neutral Dyes and Complete Photodegradation of Cationic Dyes and Antipsychotic Drugs by Lanthanide-Based Macrocycles

Molecular architectures offering large cavities can accommodate guest molecules, while their compositional engineering allows tunability of the band gap to support photocatalysis using visible light. In this work, two lanthanide (Ln)-based macrocycles, synthesized using a cobalt-based metalloligand and offering large rectangular cavities, exhibited selective adsorption of neutral dyes over both anionic and cationic dyes. Both Ln macrocycles illustrated complete photodegradation of cationic dyes using visible light without the use of any oxidant. Both Ln macrocycles exhibited complete photodegradation of not only cationic dyes but also a few phenothiazine-based antipsychotic drugs. Photocatalysis involved the generation of reactive oxygen species (ROS), which was corroborated with the band gap of two Ln macrocycles. These results were supported by radical scavenger studies and the quantitative estimation of superoxide and hydroxyl radicals. Complete photodegradation of both dyes and drugs was confirmed by spectral studies, while the generation of CO₂ and N₂ gases was established by gas chromatography. Importantly, Ln macrocycles were able to distinguish between the neutral dyes that were quantitatively adsorbed and the cationic dyes/drugs that were completely photodegraded.

Syntheses, design strategies, and photocatalytic charge dynamics of metal–organic frameworks (MOFs): a catalyzed photo-degradation approach towards organic dyes

The presented review focuses on design strategies to develop tailor-made MOFs/CPs of main group, transition and inner-transition elements and their photocatalytic properties to decompose dyes in wastewater discharge and their photocatalytic mechanism.