Fluorescence emission mechanism and fluorescence properties of ternary Tb(III) complex with diphenyl sulphoxide and bipyridine

Abstract

A novel ternary complex, TbL(5) L'(ClO(4))(3) · 3H(2)O, two binary complexes, TbL(7) (ClO(4))(3) · 3H(2)O and TbL'(3.5) (ClO(4))(3) · 4H(2)O has been synthesized (using diphenyl sulphoxide as the first ligand L, bipyridine as the second ligand L'). Their composition was analysed by element analysis, coordination titration, IR spectra and (1) H-NMR, and the fluorescence emission mechanism, fluorescence intensities and phosphorescence spectra were also investigated by comparison. It was shown that the ternary rare-earth complex showed stronger fluorescence intensities than the binary rare-earth complexes in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 8.23 times, 3.58 times as strong as that of the binary systems TbL(7) (ClO(4))(3) · 3H(2)O and TbL'(3.5) (ClO(4))(3) · 4H(2)O, respectively. By fluorescence analysis it was found that both diphenyl sulphoxide and bipyridine could sensitize the fluorescence intensities of rare-earth ions. In particular, in the ternary rare-earth complex, introduction of bipyridine was of benefit to the fluorescence properties of Tb(III).

Synthesis and fluorescence properties of 1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazol derivatives and their terbium complexes

“…The IR absorption spectra of ligands L 4 and L 6 are at 1053/cm and 1040/cm, which are attributed to the stretching vibration of the Ar‐O‐C group, but in their corresponding Tb 3+ complexes, the Ar‐O‐C group stretching frequency are red‐shifted to 1055/cm and 1044/cm, respectively. All these results indicate that the oxygen atom of Ar‐O‐C group coordinates with the rare earth ion . In the free ligands L 4 and L 6 , the C = N‐N group stretching modes is appeared at 1259/ cm ‐1 and 1243/ cm ‐1 , but the shifting of the C = N‐N stretching peak in the corresponding Tb 3+ complexes to a longer wavelength indicates involvement of the nitrogen atom of the C = N‐N group in coordination .…”

“…Pyridine‐2,6‐dicarboxylic acid (purity 99.99%, Entai Science and Technology Co., Ltd. Wuhan, China) and Tb 2 O 3 (purity 99.99%) were purchased from commercial suppliers. Tb(NO 3 ) 3 (0.2 mol/L) solution was prepared by dissolving Tb 2 O 3 (99.99%) in HNO 3 according to the literature . Monochloroacetic acid (Sinopharm Group Co., Ltd. China) and ethyl acetate were of C.P.…”

“…The procedures for synthesis of compounds 2′a–h were carried out according to the literature and partly revised by ourselves. As the synthesis methods of compounds 2′a–h were similar, only the synthesis process of the phenoxyacetic acid compound 2′a was described as an example.…”

Synthesis, characterization and properties of salicylhydrazide–salicylacylhydrazone derivatives and their terbium complexes

“…Investigation of the luminescence enhancement of terbium ions in the presence of Schiff bases is of special interest, because terbium complexes with Schiff bases are frequently used as structural and functional probes in biological systems and have technological applications in lasers, sensors and electroluminescent displays .…”