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Four novel salicyloylhydrazone derivatives and their terbium(III) complexes were synthesized and characterized. The thermal analysis results showed that the terbium(III) complexes possessed good thermal stability. The fluorescence research results showed that the terbium(III) complex substituted by phenyl possessed the best fluorescence intensity among them, and its fluorescence quantum yield was also the highest. The exploration of the electrochemical properties indicated that the introduction of electron-donating groups to the ligand can increase the highest occupied molecular orbital (HOMO) energy levels and decrease the oxidation potential of the corresponding terbium(III) complexes. The introduction of electron-withdrawing groups to the ligand can reduce their HOMO energy levels and increase their oxidation potential. The results showed that the terbium(III) complexes are good candidates for luminescent material., (© 2018 John Wiley & Sons, Ltd.) more...

A series of terbium complexes with salicylhydrazide-salicylacylhydrazone derivatives were synthesized and characterized by elemental analysis, IR spectra, UV/vis spectra and thermal analysis. The luminescence and electrochemical properties of the terbium complexes were investigated. The results show that all the target complexes exhibited characteristic emissions of terbium ions and the complex substituted by the chlorine has the strongest luminescence intensity with the highest quantum yield at 0.609. The introduction of donating electron groups could increase the oxidation potential and the highest occupied molecular orbital energy level of the terbium complex; however, the introduction of accepting electron groups gave the opposite result., (Copyright © 2015 John Wiley & Sons, Ltd.) more...

Seven novel pyrazolone derivatives were synthesized and characterized by (1) H NMR and (13) C NMR spectra, mass spectra, infrared spectra and elemental analysis. Their terbium complexes were prepared and characterized by elemental analysis, EDTA titrimetric analysis, UV/vis spectra, infrared spectra and molar conductivity, as well as thermal analysis. The fluorescence properties and fluorescence quantum yields of the complexes were investigated at room temperature. The results indicated that pyrazolone derivatives had good energy-transfer efficiency for the terbium ion. All the terbium complexes emitted green fluorescence characteristic of terbium ions, possessed strong fluorescence intensity, and showed relatively high fluorescence quantum yields. Cyclic voltammograms of the terbium complexes were studied and the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LUMO) energy levels of these complexes were estimated., (Copyright © 2014 John Wiley & Sons, Ltd.) more...

Eight novel 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazol derivatives have been designed and synthesized, and their corresponding Tb(3+) complexes were also prepared successfully. The fluorescence properties and fluorescence quantum yields of the target complexes were investigated, the results showed that the ligands were an efficient sensitizer for Tb(3+) luminescence, and the target complexes exhibited characteristic fluorescence emissions of Tb(3+) ion. The fluorescence intensity of the complex substituted by chlorine was stronger than that of other complexes. The substituents' nature has a great effect upon the electrochemical properties of the target complexes. The results showed that the introduction of the electron-withdrawing groups tended to decrease the oxidation potential and highest occupied molecular orbital energy levels of the target Tb(3+) complexes; however, introduction of the electron-donating groups can increase the corresponding complexes' oxidation potential and highest occupied molecular orbital energy levels., (Copyright © 2014 John Wiley & Sons, Ltd.) more...

A succession of Ce3+ and Tb3+ co-doped BaF2 nanoparticles were synthesized by co-precipitation and hydrothermal methods. The structure, morphology, elemental composition and photoluminescence characteristics of the doped samples were studied by X-ray diffractometry (XRD), transmission electron microscopy (TEM), X-ray energy spectrometry (EDX), photoluminescence emission spectroscopy (PL) and photoluminescence excitation spectroscopy (PLE). The phosphor has a cubic structure. According to the energy level relationship between Ce3+ and Tb3+, the energy transfer mechanism of Ce3+ and Tb3+ co-doped BaF2 samples was analyzed. Ce3+, Tb3+ co-doped BaF2 shows a strong green emission, and its fluorescence emission intensity is about 9 times higher than that of Tb3+ single doped BaF2. The energy transfer efficiency from Ce3+ to Tb3+ was calculated using a formula, and it was found that the energy transfer efficiency could reach up to 88.22%. The detection solution was prepared by uniformly dispersing the phosphor in absolute ethanol. Through a comparative study of a series of metal ions, it was found that the detection solution has a peculiar sensitivity to aqueous solutions containing Cu2+. At the same time, the relationship between the fluorescence intensity of the detection solution and the concentration of Cu2+ was studied, and the cause of fluorescence quenching caused by Cu2+ ions was analyzed from the perspective of energy transfer. From this work, it is considered that the phosphor has a great potential application in the determination of Cu2+ in practical wastewater. [ABSTRACT FROM AUTHOR] more...

A series of coumarin derivatives obtained from salicylaldehyde and phenol were synthesized. Their corresponding terbium complexes were prepared and characterized by elemental analysis, EDTA titrations, molar conductivity, UV-vis spectra, IR spectra, and thermal analysis. The luminescent properties and electrochemical properties of the terbium complexes were also investigated. The results showed that all the terbium complexes exhibited characteristic emissions of terbium ions. The introduction of electron-donating groups can improve the luminescent properties, decrease the HOMO and LUMO energy levels of the terbium complex, while electron-withdrawing groups can weaken the luminescent properties, and increase the HOMO and LUMO energy levels of terbium complex. [ABSTRACT FROM AUTHOR] more...

A succession of single-phase SrF 2 : Tb3+, Eu3+ phosphors with adjustable output colour were prepared via chemical co-precipitation technique. The crystal structure, scanning electron microscopy (SEM), photo-luminescence excitation (PLE) spectrum, photo-luminescence emission (PL) spectrum, photo-luminescence decay curve and thermal stability studies were used to analyze systematically the energy transfer (ET) properties in SrF 2 host. SrF 2 :Eu3+ phosphors present an obvious orange fluorescence and SrF 2 :Tb3+ phosphors exhibit the characteristic green fluorescence. The optimal single dopant contents of Eu3+ and Tb3+ are 7 mol% and 6 mol%, respectively. By optical analysis, it can be inferred that Eu3+ and Tb3+ may mainly occupy the reverse symmetric position. Moreover, in the 6 mol%Tb3+, zmol% Eu3+ co-doped SrF 2 samples, the intensity of terbium ions characteristic emission (545 nm) decreases monotonically and europium ions characteristic emission (592 nm) increases monotonously by elevating amounts of Eu3+ contents. Thus the alteration of light output colour from green to yellow and definitively to orange can be observed via appropriately adjusting Eu3+/Tb3+ ratios. ET type was testified in SrF 2 host is a quadrupole-quadrupole mechanism. Additionally, the critical distance of ET from terbium to europium, which was calculated by quenching concentration method, was 10.521 Å. Meanwhile, the SrF 2 : 6 mol% Tb3+, 1 mol% Eu3+ exhibits a good thermal stability, so, it will have potential applications for n-UV w-LEDs. Image 1 [ABSTRACT FROM AUTHOR] more...

Six new 4-acyl pyrazolone derivatives and their complexes with the terbium nitrates were synthesized and characterized by mass spectra, elemental analysis, EDTA titrimetric analysis, UV spectra, infrared spectra, molar conductivity and thermal analysis. The results showed that pyrazolone derivatives formed good coordination with the terbium ions. The introduction of electron-donating group in the ligands not only increased the luminescence intensity and fluorescence quantum yield, but also enlarged the HOMO and LUMO energy levels of corresponding terbium complexes. All the complexes possessed high luminescence intensity and showed relatively high fluorescence quantum yields. These target complexes may have vast potential to be developed as luminescence materials in the future. [ABSTRACT FROM AUTHOR] more...

A series of Sr 2 CeO 4 :2%Eu3+ doped with different metal ions M2+ (M=Mg, Ba, Ca) were synthesized through hydrothermal method. the related phosphors could emit pure red light under being excited with blue light (467 nm), which could be one good alternative for application in blue-excited WLEDs. [Display omitted] • Sr 2 CeO 4 is one kind excellent blue-white-emitting oxide-based phosphor and its emission is due to the Ce4+–O2- charge transfer under a broad excitation band in the UV range. • A series of Sr 2 CeO 4 :xEu3+ (x = 0.15, 1, 2, 5 mol%) (SCO:xEu3+) and co-doped with different divalent metal ions (M2+: Mg, Ca, Ba) phosphors were designed through traditional hydrothermal method. • When the concentration of Eu3+ ion goes up to 2 %, the sample exhibits the emission of Ce-O CTS at weak intensity and the emission of Eu3+ ion at higher intensity. • When co-doping with 2 %M2+, the related samples present only emission of Eu3+ ions under blue light excitation with good color purity. In the present work, A series of Sr 2 CeO 4 :xEu3+ (x = 0.15, 1, 2, 5 mol%) (SCO:xEu3+) and co-doped with different divalent metal ions (M2+: Mg, Ca, Ba) phosphors were successfully synthesized through traditional hydrothermal method. All the samples performed pure Sr 2 CeO 4 phase. The absorption spectra show that an overlap between Ce4+–O2- CTS band and Eu3+ ions results in the energy transfer from the matrix to the emitting center. With the concentration of Eu3+ ion increasing, the phosphors exhibit orange red emission, and the highest intensity was achieved when the Eu3+ concentration was 2 mol%. The energy transfer mechanism would be dipole–dipole interaction. Furthermore, when the concentration of Eu3+ ion is at 2 mol%, the samples co-doped with M2+ ion performed intense red emission of Eu3+ ion under 467 nm excitation, which is ascribed to M2+ ions disturbed the anisotropic structure to create defects so that make much more efficient energy transfer from Ce-O band to Eu3+ ions. Moreover, CIE chromaticity showed SCO:2%Eu3+/2%M2+ phosphors performed pure red warm light. The above results suggest that SCO:2%Eu3+/2%M2+ can be of potential as red-emitting phosphor for blue-excitation WLEDs. [ABSTRACT FROM AUTHOR] more...

Six amide-based open-chain crown ether and their solid complexes with terbium nitrates were synthesized. The target complexes were characterized by elemental analysis, mass spectra, EDTA titrimetric analysis, thermal analysis, molar conductivity, infrared spectra and UV–vis spectra. Luminescence properties of the ligands and the corresponding complexes in solid were studied. The results showed that the introduction of electron-donating group to the ligand enhanced the luminescence intensity of the corresponding complex, but electron-withdrawing group conversely. Meanwhile, among all complexes, the luminescence quantum yield of the complex Tb(NO 3 ) 3 Y 1 was highest up to 0.76. Electrochemical properties were also investigated, and the results showed that the introduction of electron-donating group to the ligand enhanced the highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) energy level, but electron-withdrawing group conversely. And these target complexes may possibly be useful for studying in organic light-emitting devices field. [ABSTRACT FROM AUTHOR] more...