LAUSR

Abstract In this study, principally novel lanthanide organic complexes Eu (TTA)2Phen (β-T) (LCA-D)containing Eu3+ ions, thenoyltrifluoroacetone (TTA), 1,10-phenanthroline (Phen), and β-thujaplicin (β-T) have been fabricated. Their fluorescence features were compared with those of Eu (TTA)3Phen (LCA-C) complexes, which are well-known light-emitting materials. The molecular and crystalline structures of complexes LCA-C and LCA-D were explored using nuclear magnetic resonance spectroscopy (1HNMR), Fourier transform infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD). The optical properties of these complexes were also explored using ultraviolet–visible spectroscopy (UV–Vis), fluorescence spectra, and absolute photoluminescence quantum yield (PLQY). The obtained results showed that LCA-D possessed an intense absorption peak at wavelength about 239 nm and a weak absorption peak within a spectral range 250–375 nm with respect to LCA-C. LCA-D possesses a sharp red emission at λ = 615 nm upon excitation at λ = 348 nm, which was assigned to the electronic intra-center transition of 5D0-7F2 of Eu3+ ions. After the addition of β-T, the intensity of emission peak at λ = 700 nm has been enhanced for LCA-D. The magnitude of QY for LCA-D was equal to about 23.91%, which was at least 11.4% higher than that of LCA-C. The thermal features tested for TG-DTG-DSC also indicated that LCA-D exhibited a promising temperature stability at ambient temperature up to 280 °C, which was suitable for agricultural film processing.