Content Of Tb3 Research Articles

Temperature-Sensitive Chameleon Luminescent Films Based on PMMA Doped with Europium(III) and Terbium(III) Anisometric Complexes

The spin-coating technique was used to produce composite films consisting of PMMA polymer doped with anisometric complexes of Eu(III) and Tb(III). It was found that an increase in the content of Tb3+ complexes intensifies emission of both ions due to the intermolecular energy transfer from the Tb(III) complex to the Eu(III) complex, which results in the increase in the relative luminescence quantum yield of Eu(III) ion by 36%. The temperature sensitivity of the film luminescence intensity and lifetime in the range of 296–363 K was investigated. The maximum relative sensitivity of the films reaches 5.44% × K−1 and exceeds that of all known lanthanide-containing thermal sensors designed for measuring physiological temperatures. In combination with changing luminescence color, such a sensitivity makes these films promising colorimetric thermal sensors for in situ temperature measurements.

Lanthanide-doped heterostructured nanocomposites toward advanced optical anti-counterfeiting and information storage

The continuously growing importance of information storage, transmission, and authentication impose many new demands and challenges for modern nano-photonic materials and information storage technologies, both in security and storage capacity. Recently, luminescent lanthanide-doped nanomaterials have drawn much attention in this field because of their photostability, multimodal/multicolor/narrowband emissions, and long luminescence lifetime. Here, we report a multimodal nanocomposite composed of lanthanide-doped upconverting nanoparticle and EuSe semiconductor, which was constructed by utilizing a cation exchange strategy. The nanocomposite can emit blue and white light under 365 and 394 nm excitation, respectively. Meanwhile, the nanocomposites show different colors under 980 nm laser excitation when the content of Tb3+ ions is changed in the upconversion nanoparticles. Moreover, the time-gating technology is used to filter the upconversion emission of a long lifetime from Tb3+ or Eu3+, and the possibilities for modulating the emission color of the nanocomposites are further expanded. Based on the advantage of multiple tunable luminescence, the nanocomposites are designed as optical modules to load optical information. This work enables multi-dimensional storage of information and provides new insights into the design and fabrication of next-generation storage materials.

Influence of Tb3+ ions concentration and temperature on lithium bismuth alumino borosilicate glasses for green photonic device applications

Lithium bismuth alumino borosilicate (LiBiAlBSi) glasses doped with various concentrations of trivalent terbium (Tb3+) ions were prepared to explore their physical, optical, and photoluminescence (PL) characteristics features. Diffraction pattern recorded for an undoped as well as doped (1.5 mol% of Tb3+) LiBiAlBSi glass ascertained the amorphous nature. Absorption spectra reveal several peaks in n-UV and blue regions. The indirect optical band gap for Tb3+ doped LiBiAlBSi glasses was found in the 3.16-3.46 eV range. PL measurements such as emission (under 378 nm excitation) and excitation (under 542 nm emission) were recorded to study the usage of the as-prepared glasses for green photonic device applications. PL emission spectra reveal four emission bands of Tb3+ ions originating from the excited level of 5D4 to 7FJ (=3,4,5,6) levels. The intensity of the emission peak observed in the green region at 542 nm (5D4→7F5) escalates up to 1.5 mol% of Tb3+ ion concentration and declines beyond due to concentration quenching. Dexter theory applied to the PL emission spectral features reveals dipole-dipole interaction among Tb3+ ions responsible for the transfer of energy and thereby concentration quenching. The CIE coordinates and CCT values calculated for the as-prepared glasses are closure to the values of intense green emission given by the European Broadcasting Union illuminant. The experimental lifetime values (τexp) measured for the intense green emission (5D4→7F5) are reducing with the upsurge in the content of Tb3+ ions in the titled glasses. Correlation of τexp values with the PL emission spectral data facilitate the estimation of radiative properties. Relatively high activation energy value estimated from the temperature-dependent PL show the thermal stability of the optimized glass. The PL (excitation, emission, decay, temperature-dependent) studies along with colorimetric studies confirm the aptness of the LBiAlBSiTb15 glass for photonic applications such as laser and tricolour w-LEDs as a green emitting component.

Relationship of Various Structural Parameters with Magnetic Behavior of Stoichiometric Tb3+ and Dy3+ Co-substituted NiFe2O4 Nanostructures

In this study, we have successfully controlled the structural parameters of NiFe2-x-y TbxDyyO4 (x + y = 0, 0.1, 0.15, 0.2) of nickel ferrites with the substitution of rare earth metal ions (RE3+ = Tb3+, Dy3+) in order to optimize the magnetic properties. XRD reflections had ensured phase purity and single phase of FCC structure formation for all synthesized samples with no additional impurity peaks. It was found that crystallite size and lattice parameters are found to decrease from 28.13 to 25.2 nm and 8.43 to 8.41 A, respectively, with increasing the amount of dopant ions. The magnetic parameters for NiFe2-x-yTbxDyyO4 (x + y = 0, 0.1, 0.15, 0.2) were measured by tracing the hysteresis curves for all synthesized samples at room temperature. VSM data suggested a decrease in magnetization which is attributed to increase in spin disorder due the decrease of crystallite size which was associated with increase in contents of Tb3+, Dy3+ ions in the host structure. Higher dopant concentrations have greatly reduced coercivity and improve initial permeability. Hence, size and shape of particles are the key features which govern the stability and magnetic properties of ferrite nanoparticles.

Tunable white light emission of rare earth ions doped single matrix SrAl2Si2O8 phosphors

Aluminosilicate phosphors have been successfully applied in laser technology and fluorescent lamps due to their high luminescence properties and excellent chemical stability. Consequently, research on novel aluminosilicate phosphors has a good application prospect. Rare earth (RE) ions doped SrAl2Si2O8 phosphors were prepared by solid-phase method. Excited at 350 nm, the phosphor doped with Dy3+ ions emits a blue light peaking at 482 nm and an orange light peaking at 575 nm, respectively, and its optimum doping concentration is 0.8 at.%. At the NUV excitation of 377 nm, the phosphor doped with Tb3+ ions shows emission peaks at 489 nm, 544 nm, 585 nm and 623 nm, and the luminescence intensity is the strongest when the content of Tb3+ is 9 at.%. The concentration quenching mechanism of Dy3+ and Tb3+ RE ions is the electric dipole–dipole interaction. For SrAl2Si2O8:Tb3+, Sm3+ phosphors, the energy transfer efficiency is 85.4%, and the mechanism is electric dipole–quadrupole interaction. For SrAl2Si2O8:Dy3+ and SrAl2Si2O8:Tb3+, Sm3+ phosphors, the best CIE coordinates are (0.275, 0.308), (0.316, 0.386). The consequences display that RE ions doped single matrix SrAl2Si2O8 phosphors can achieve effective white light emission and have high application value in white LEDs.

The luminescent properties of GdAlO<SUB align="right">3:Tb<SUP align="right">3+</SUP> phosphors based on molten salts addition

The (Gd1−xTbx)AlO3 (x = 0-0.12) were obtained through ammonium bicarbonate co-precipitation technology. The pure-phase (Gd1−xTbx)AlO3 with good dispersion could be obtained at relatively lower temperature of 1,000°C. Under optimum UV excitation into 275 nm, the photoluminescence (PL) spectra display a series of 5D4−7FJ transitions of Tb3+ in (Gd1−xTbx)AlO3 system with the strongest green emission at ~546 nm. The overlapping between 8S7/2−6IJ intra f-f transition of Gd3+ and 4f8-4f75d1 transition of Tb3+ at 275 nm suggesting the Gd3+ → Tb3+ energy transfer, and the quenching contents of Tb3+ was found to be ~10 at%. The luminescent property of GdAlO3:Tb3+ phosphor could be further improved with molten salt incorporation. The optimal composition of molten salts was determined to be the mixture of NaCl/Na2SO4 (5 wt% NaCl), and the mass ratio of mixture molten salts to precursor was 2:1. The relationship between the luminescent property and molten salts composition were studied in detail.

Study on structure and fluorescence of Tb-doped CaAl LDHs prepared in ethanol/water system

An important material applied in biological fluorescent detector and medical treatment is highly desired in view of the biocompatibility and fluorescent property. Here, Tb-doped CaAl-layered double hydroxides with Ca2+/(Al3+ + Tb3+) molar ratio of 1.0, 2.0, 3.0, and 4.0 have been successfully prepared in a mixed solution of ethanol and water in a reasonable proportion. Chemical compositional analyses revealed that the experimental value of Ca2+/(Al3+ + Tb3+) molar ratio present in the samples was close to the initial value of Ca2+/(Al3+ + Tb3+) molar ratio of raw reactants. In the X-ray diffraction results, it was found that the typical layered double hydroxides structure can be kept between the Ca2+/(Al3++Tb3+) molar ratio of 1.0 and 4.0. The structural type of the Tb-doped CaAl-layered double hydroxides was monoclinic form when the Tb content was less than of 3.0 %, while rhombohedral form appeared and retained as the content of Tb3+ is kept between 3.0 and 5.28 wt%. Photoluminescence shows strong green emissions attributed to 5D4-7FJ (J = 3, 4, 5, 6) transition of Tb3+ ions incorporated in the Tb-doped CaAl-layered double hydroxides. A series of Tb-doped CaAl-LDHs with different molar ratio of Ca2+/(Al3+ + Tb3+) have been synthesized by co-precipitation in a mixed ethanol/water system. Strong green emission appeared in the Tb-doped CaAl-LDH. The Tb–CaAl-LDHs may be a promising biological fluorescent material because of the biocompatibility of Ca2+ ions as well as the fluorescent property of Tb3+ ions.

Fabrication of Polyaniline/Graphene/Tb3+ Conductive Composite Material

Polyaniline/graphene/Tb3+(PANI/GN/Tb3+) composite material was successfully prepared by the method of in-situ polymerization. The morphology of this as-formed composite material has been confirmed by scanning electron microscope (SEM) analysis. SEM images illustrated that the PANI were uniformly deposited on GN nanosheets. PANI/GN/Tb3+ composite material exhibited high electrical conductivity than the pristine PANI. What's more, results also demonstrated that the synthesized composite material has found wide promising applications in capacitors. Finally, the conductive mechanism of PANI/GN/rare earth composite is discussed in this paper, the conductivity of nanocomposites offered upgrade first than descending latter tendency with different content of Tb3+ ions. The results should be attributed to the special electronic structure and excellent magnetic of rare earth ions, which can influence the polymer chains.

Synthesis and Characterization of Tb3+-Doped HA Nanoparticles Used as Biological Florescent Probe

A biological florescent probe Tb3+-doped hydroxyapatite (HA) nanoparticles was synthesized by hydrothermal method. During this process, L-lysine was added as a template, and different amount of Tb3+was added to investigate the influence on the florescent property. The products were characterized by using XRD, TEM and PL. Results showed that with Tb3+adding, the size and crystallinity of nanoparticles were changed, while their maximum emission intensity was at 544 nm and the best content of Tb3+was 2 mol%.

Different luminescent behaviors between photoluminescence and persistent luminescence in Tb3+ doped Li2CaGeO4 phosphors

Different contents of Tb3+ ions doped Li2CaGeO4 phosphors were prepared successfully by the traditional high temperature solid-state reaction method. The influences of Tb3+ ions concentrations on photoluminescence (PL), long persistent luminescence (LPL) and thermoluminescence (TL) properties were studied systematically. The cross-relaxation of Tb3+ in Li2CaGeO4 host was observed in PL when the doping concentration of Tb3+ exceeded 2% but not in LPL. The optimal concentration of Tb3+ for LPL was about 1%. The escaped charge carriers from shallower trap can be re-trapped by deeper traps. A tentative schematic was proposed to illuminate the mechanism of LPL. Besides, the different luminescent behaviors of Tb3+ in Li2CaGeO4 host between PL and LPL were also discussed accordingly.

A novel photoluminescent nanohybrid of poly(ε-caprolactone) grafted Mg/Al layered double hydroxides and Tb3+ ions: Synthesis and characterization

This paper demonstrates a systematic study of the synthesis and characterization of the hybrid of Mg–Al layer double hydroxides (LDHs), poly(ε-caprolactone) (PCL), and terbium ions (Tb3+). The hybrid LDH-g-PCL-Tb3+-1,10-phenanthroline (Phen) was prepared by the combination of ring opening polymerization (ROP), click chemistry, and coordination chemistry. First, LDHs with a molar ratio of Mg/Al = 2 were prepared by the co-precipitation method, which was subsequently functionalized with (3-chloropropyl) trimethoxysilane in order to introduce azide groups through the reaction of chlorine with sodium azide. Meanwhile, the acetylene functionalized PCL was prepared by ROP of ε-CL, followed by esterification of the hydroxyl groups using succinic anhydride. The click reaction of alkyne-PCL and N3-LDHs successfully afforded LDH-g-PCL, which was coordinated with Tb3+ ions in the presence of Phen. The structure and properties of the nanohybrids were investigated by FT-IR, XPS, EDS, SEM, and TGA analyses. The data indicate the coordination of Tb3+ ions with LDH-g-PCL nanohybrids. The content of Tb3+ ions in the LDH-g-PCL-Tb3+-Phen complex was calculated to be 8.7% (w/w). The LDH-g-PCL-Tb3+-Phen complexes showed four emission bands with high fluorescence intensity centered at 489 nm (5D4 → 7F6), 546 nm (5D4 → 7F5), 586 nm (5D4 → 7F4) and 623 nm (5D4 → 7F3) with excitation at 328 nm (3F6 → 5G6). The stability of LDH-g-PCL-Tb3+-Phen complexes under UV irradiation was high, and no leaching effect was observed.

Enhanced photoluminescence properties of CaYBO4:Tb3+,Al3+ by doping Al3+ for plasma display panel applications

The effect of photoluminescence properties for (CaY)1−x−yTbxAlyBO4 phosphors was studied, considering the doped Al3+ and Tb3+ contents. The emission intensity of the Al3+-doped (CaY)0.915Tb0.06Al0.025BO4 phosphors under VUV excitation was more than two times stronger than that of the Al3+-free (CaY)0.94Tb0.06BO4. The contents of Tb3+ showing the strongest emission for the (CaY)0.975−xTbxAl0.025BO4 and (CaY)1−xTbxBO4 phosphors were x = 0.1 and 0.12, respectively. The results confirm that incorporating Al3+ in (CaY)1−xTbxBO4 phosphors is highly favorable for improving emission characteristics, along with production cost-effectiveness.

Transition from spin ice to spin liquid——evolvement of structure and magnetic properties

The polycrystal samples of Ho2-xTbxTi2O7（x=0，05，1，15，2） were prepared by solid reaction method. The result of X-ray diffraction （XRD） and dc susceptibility measurement from 2 K to 300 K both indicate that as the content of Tb3+，i.e. x，increases，the system crosses over from Ho2Ti2O7spin ice to Tb2Ti2O7 spin liquid，the lattice constant of cubic pyrochlore increases，while the Curie constant and effective magnetic moment decrease. Especially，the Curie-Weiss temperature decreases from positive to negative with the decrease of x，implying the transition from ferromagnetic Ho2Ti2O7 to anti-ferromagnetic Tb2Ti2O7. The detailed analysis shows that as x in Ho2-xTbxTi2O7 increases，the intensity of long-range dipolar interaction Dnn decreases. Being ferromagnetic or anti-ferromagnetic，and the change in intensity of long-range dipolar interaction, may be the two crucial factors influencing on the system to form spin ice state or cooperative paramagnetic state，i.e. the spin liquid state.

Structure and Luminescence Properties of New Green-Emitting Phosphor BaAl12O19:Tb

New green-emitting BaAl12O19:Tb phosphors were prepared by using the sol–gel method, and their structure and luminescence property were characterized by X-ray diffraction (XRD) analysis and fluorescence spectrometry. The results of XRD analysis revealed that a Ba1-xAl12O19:Tbx crystal structure was obtained at 1300 °C and Tb3+ ions substituted Ba2+ ions into the BaAl12O19 phase in the ion range x=0.005–0.05. The excitation peak of BaAl12O19:Tb was a wide band at approximately 240 nm, originating from the 4 f8–4 f75d1 transition of Tb3+. The emission spectrum consisted of eight emission peaks, originating from the 5D3–7Fi (i=6,5,4,3) and 5D4–7Fj ( j=6,5,4,3) transitions of Tb3+. The emission intensity of BaAl12O19:Tb phosphors at 543 nm was strongest when the phosphors were crystallized at 1300 °C for 2 h, and the content of Tb3+ was 2 mol %.

Analysis of the laser performance of Tm 3+ : ZBLAN glass at 1.47 m wavelength

A formula for the threshold energy of a four-level-system laser in Tm3+ doped fluoride glass is derived. The formula contains the parameters of the interaction between the ions and the up-conversion rate of the pump-light. It is discussed that the Tb3+ ions and the up-conversion pump-light have an influence on the laser performance of Tm3+ ions around 1.47μm wavelength. We draw the following two conclusions. (1) The laser threshold descends obviously due to the doping of Tb3+ ions, but the descending gradually flattens out with the increase of the content of Tb3+ ions. Its suitable content is (1–2)×1020cm−3. (2) When pump-lights both from the up-conversion and from the ground state excite simultaneously the single-doped Tm3+ ions, the threshold energy can reduce and the output energy can increase. In this paper, the energy conversion efficiency from the up-conversion pump-light to the output energy of laser is estimated.