Synthesis and luminescence properties of ternary complexes of Sm _x Tb_1−x (TTA)₃Phen nanoparticles and their surface modification

A series of Sm _x Tb_1−x (TTA)₃Phen (x = 1.0, 0.9, 0.7, 0.5, 0.3, 0.1, 0) complexes was synthesized by wet chemical method and characterized using Fourier transform infrared spectroscopy and fluorescence spectroscopy. The IR absorption spectra indicate that α-thenoyltrifluoroacetone was coordinated to the rare earth ions and that chemical bonds were formed between rare earth ions and the nitrogen atoms in 1,10-Phenanthroline (Phen). The fluorescence spectra of the complexes indicate that the emission intensity of Sm³⁺ was enhanced by the addition of substitutive Tb³⁺. These data show that not only the ligands (TTA and Phen) but also Tb³⁺ could absorb and transmit energy to Sm³⁺ in the complexes. Formation of dual-core complexes appears to be responsible for co-fluorescence, which can greatly promote the illuminant ability of Sm (TTA)₃Phen complex. After further encapsulation by SiO₂, the Sm _x Tb_1−x (TTA)₃Phen@SiO₂ core–shell structure was very stable to UV light.