Investigation of the Photophysical Properties of Green Light-Emitting Tb(III) Complexes with 6-Fluoro-3-Formylchromone and N, N & PRIME;-Donor Heterocyclic Secondary Ligands for Their Potential Applications in Optoelectronic Devices

Luminescent Tb(III) complexes with organic ligands have shown great potential for use in optoelectronic devices due to their strong luminescence, long emission lifetimes, and narrow emission bands. In this study, we report the synthesis, characterization, and photophysical properties of a series of Tb(III) complexes with the organic ligand 6-fluoro-3-formylchromone (FFC) and heterocyclic neutral auxiliary ligands. The complex was characterized using UV-visible spectroscopy (UV-Vis), elemental analysis, Fourier-transform infrared spectroscopy (FTIR), thermal studies, mass spectrometry, powder x-ray diffraction studies (PXRD), and photoluminescence (PL) spectroscopy. The results indicate that the complex has a high quantum yield (& phi;(Tb) = 56.89%), longer lifetime period (& tau;(obs) = 0.892 ms), intrinsic quantum yield (& eta;(Tb) = 29.73%), and radiative rate and green luminescence with a radiative decay rate of (K-Rad) 6.36 x 10(2) s(-1). The UV-vis absorption spectra showed that the complex has strong absorption in the UV region, and the FTIR spectra confirmed the formation of the complex. The thermal studies revealed that the complex is stable up to 180 & DEG;C, and the mass spectrometry and elemental analysis confirmed the molecular formula of the complex. PXRD study showed that the complex has a crystalline structure with a particle size in the nanometer range. The PL spectroscopy showed that the complex has a high luminescence intensity and a long emission lifetime. Overall, the results suggest that the Tb(III) complex with FFC is a promising candidate for use in optoelectronic devices.