Photo-Physical, Optical and Antimicrobial Properties of Eu(III) Complexes with TPB by Using Different Auxiliary Ligands.

A series of four bright red Eu(III) complexes are reported here, with the general formula [Eu(L)₃.auxiliary] where L is 4,4,4-trifluoro-1-phenyl-1,3-butanedione (TPB) whereas auxiliary ligands are the N-donor heterocyclic aromatic systems. The solution precipitation method was used to synthesize these complexes, and Elemental analysis, EDAX, TEM, XRD, UV, FTIR, NMR, and SEM techniques were used for characterization. The results of investigations indicated that complexes between the metal ion, diketonic moiety, and auxiliary ligands had been successfully synthesized. The thermal stability of complexes is determined by TGA/DTA. The complexes showed excellent luminescence in both the solid and solution phases. Hypersensitive ⁵D₀ → ⁷F₂ transition is responsible for bright red color emitted by complexes on exposure to UV rays. J-O analysis asserted the asymmetrical coordination surrounding of Eu(III) ion in complexes. Various radiative properties (A_rad, A_NR, β_exp) and band gap values were also determined, which revealed the applicability of complexes in diverse optoelectronic domains. The complexes in the solid and solution phases show high color purity (> 90%). However, CCT value unveiled use of the complexes as a warm light source. All of the studies confirmed the complexes have exquisite luminosity, which makes them even more promising as a luminescent material for a variety of applications. All complexes show good antimicrobial properties.