Tb Ions Research Articles

Ultra-low concentration terbium (Tb) adsorption on garlic peels biosorbent and its application for Nd-Fe-B scraps recovery

Motivated by the strategic value of middle-heavy rare earth elements (MHREEs), we proposed a bio-adsorption method to recover ultra-low concentration terbium (Tb(Ⅲ)) from industrial wastewater that originated from the Nd-Fe-B scraps recovery process. It could be found that Tb(Ⅲ) ions as low as 5.34 ng·mL−1(ppb) could be adsorbed onto Ca(Ⅱ)-modified garlic peels (Ca-GP) within 10 min with the adsorption efficiency of 99.2% at pH 3.5. The adsorption behavior of Tb(Ⅲ) onto Ca-GP conformed the Langmuir isotherm model and pseudo-second-order kinetic model. ATR-FTIR, XPS and density-functional theory (DFT) calculations results showed that Tb(Ⅲ) ions could be ion-exchanged with cations in Ca-GP such as Ca(Ⅱ) and -COOH. In application, column experiment results showed that the maximum bed adsorption capacity for Tb, praseodymium (Pr), neodymium (Nd), dysprosium (Dy), and Total rare earth elements (REEs) ions calculated by the Thomas model was 0.06, 3.50, 9.65, 7.34, and 27.37 μg·g−1, respectively, with the initial concentration of 0.37 ng·mL−1 Tb, 20 ng·mL−1 Pr, 44 ng·mL−1 Nd, 67 ng·mL−1 Dy and 170 ng·mL−1 total REEs ions of actual solutions (below the solubility of rare-earth hydroxide). This manuscript thus provided a novel cost-effective and efficient approach to the enrichment and recovery of MHREEs from ultra-low concentration REEs ions-containing solutions.

Multiple magnetic phases and magnetization plateaus in TbRh6Ge4

We probe the magnetic order in single crystals of $\mathrm{Tb}{\mathrm{Rh}}_{6}{\mathrm{Ge}}_{4}$ using electrical transport, magnetization, and thermodynamic measurements. $\mathrm{Tb}{\mathrm{Rh}}_{6}{\mathrm{Ge}}_{4}$ crystallizes in the noncentrosymmetric tetragonal $\mathrm{Li}{\mathrm{Co}}_{6}{\mathrm{P}}_{4}$-type structure, where the Tb ions form a triangular lattice in the basal plane and chains along the $c$ axis. This compound undergoes a second-order antiferromagnetic transition at ${T}_{N}=12.7$ K, which is followed by an additional transition at ${T}_{M}=2.8$ K. When fields are applied along the easy $c$ axis, multiple metamagnetic transitions are observed, where there are plateaus at 1/9 and 1/3 of the saturation magnetization. We map the field-temperature phase diagram revealing complex magnetism, where antiferromagnetic coupling within the basal plane may lead to significant magnetic frustration.

Studies on the effect of In3+ ion on magnetic and magneto caloric properties of polycrystalline TbMnO3

Polycrystalline Tb1−xInxMnO3 (x ​= ​0.0, 0.05, and 0.075) compounds, have been prepared using conventional solid state reaction method. Their structural, magnetic, and magnetocaloric properties are studied using the Powder X-ray diffraction, RT-Raman spectroscopy, low temperature magnetization measurements. The X-ray powder diffraction analysis reveals that these compounds crystallized in orthorhombic structure with space group (Pbnm). The structural analysis showed that the two lattice parameters (a, b) in the basal plane slightly decrease while the axial lattice parameter (c) remains unchanged with increase of In doping. Overall reduction in the cell volume indicates the substitution of In ions for Tb ions. A weak AFM ordering has been observed in the magnetic measurements for all the three compounds due to the ordering of Tb3+ moments. External magnetic field induced meta-magnetic transition for all the compounds. The maximum isothermal entropy change - ΔSMmax for the field value of 7 ​T was observed to be 8.72 ​J/Kkg,7.46 ​J/K kg and 7.07 ​J/K kg for x ​= ​0.0, 0.05, and 0.075 respectively.

Canting Angle Behavior of Magnetic Moments in Y‐Substituted Tb2BaNiO5 and Its Relevance for Magnetoelectric Coupling

The Haldane‐spin chain compound, Tb2BaNiO5, has been known to be an exotic multiferroic system, exhibiting antiferromagnetic anomalies at T N1 = 63 K and T N2 = 25 K, with ferroelectricity appearing below T N2 only. Previous reports in addition have established that, interestingly, Tb ions play a direct and decisive role to lead to multiferroic properties with a critical canting angle of magnetic moments, unlike other well‐known multiferroics. Herein, the results of temperature‐dependent neutron powder diffraction studies on Tb2–x Y x BaNiO5 are reported, to get an insight into the critical canting angle for multiferroic behavior. While multiferroic transition temperature decreases linearly with Y concentration, there is an abrupt drop of relative canting angle (of Tb and Ni magnetic moments) with respect to that in the parent compound for an initial substitution of x = 0.5 in the multiferroic region, without any notable change thereafter. Therefore, it is inferred that this critical canting angle is made up of two components—cooperative (long‐range) and local (short‐range) contributions.

Unclonable fluorescence of MgO-ZrO2 :Tb3+ nanocomposite for versatile applications in data security, dermatoglyphics.

Latent fingerprints (LFPs) are one among the most important types of evidences at crime scenes because of the distinctiveness and tenacity of the friction ridges in fingerprints (FPs). Therefore, it is essential in forensic science to develop a reliable method to detect LFPs. Traditional detection methods still face a number of difficulties, such as limited sensitivity, low contrast, strong background, and complex processing stages. In this study, MgO-ZrO2 :Tb3+ (1-5mol%) (MZ:Tb) nanocomposites (NCs) were prepared via a simple solution combustion (SC) method at low temperature. The photoluminescence (PL) investigation demonstrates that when excited at 379 nm, the produced NCs emits distinctive emission peaks of terbium ions (Tb3+ ). According to the photometric results, the NCs can be employed as warm light NCs and emit light in the green portion of the colour spectrum. The estimated optical band gap from diffuse reflectance spectra is found to be in the range 4.84-4.97 eV. Regardless of the type of surface being used, the optimized MgO-ZrO2 :Tb3+ (4mol%) (MZ:4Tb) NCs has a strong ability to minimize background fluorescence interference. With high contrast LFP and I-V type of cheiloscopy, these NCs present a flexible fluorescent mark for the identification of levels 1-3 details in forensic investigation.

The Effect of Alkali-Fluoride on the Photoluminescence Properties of Tb3+ Doped on Phosphate Glass Medium

The effect of alkali fluoride on the photoluminescence properties of Tb3+ doped on the phosphate glass was discovered. However, the composition of the glass samples were 20Li2O–10AlF3–69P2O5–1Tb2O3 (LAPTb) and 20Li2O–10AlF3–10NaF–59P2O5–1Tb2O3 (LANPTb). To study optical properties were examined through their absorption and luminescence spectra. Luminescence spectra were investigated by photoluminescence. Characteristic luminescence bands corresponding to electronic transitions of terbium ions (Tb3+) were detected under two direct excitations of Tb3+ ions. Upon 377 nm excitation, the glass samples were obtained transition terbium 5D4 → 7F5 at 544 nm showed a green laser. The decay time Tb3+ for the 5D4 level has been confirmed and the result was 2.865 ms and 2.982 ms corresponding to LAPTb was LANPTb, respectively. The green laser application has been investigated by a CIE-color-coordinates diagram with a color purity is ~73%.

SYNTHESIS AND PROPERTIES OF NANODISPERSED LUMINESCENT STRUCTURES BASED ON LANTHANUM FLUORIDE FOR OPTOPHARMACOLOGY AND PHOTODYNAMIC THERAPY

Nanocrystalline lanthanum fluoride of hexagonal syngonium and terbium-activated lanthanum fluoride were synthesized. The structural characteristics of the synthesized samples were investigated by XRD, TEM, FTIR, PCS methods. The colloidal stability of the suspensions and the acid-base characteristics of the surface were evaluated in the environment of physiological solution.
 Substitution of La ions by Tb ions in LaF3:Tb samples does not lead to a significant distortion of the crystal structure, but it significantly affects the dimensional characteristics, specific surface area, charge and acid-base characteristics.
 The given data indicate the perspective of research of nanodispersed phosphors based on lanthanum fl uoride for use in optopharmacology and photodynamic therapy of tumor diseases localized in the organ s of the skull and bone tissues. In addition, research results can be useful for technical applications, in particular, in the creation of fluorescent detectors of high-energy electromagnetic radiation, development of photo- and optoelectronic devices, etc.

Terbium-triggered aggregation-induced emission of bimetallic nanoclusters for anticancer drugs sensing via the inner filter effect

The development of accurate and sensitive detection methods of anticancer drugs is of significant importance because they play vital roles in biological systems. In recent years, bimetallic nanoclusters (BMNCs) incorporating the advantages of two metals have gained more and more attention, and can be widely applied in sensing applications. In this work, for the first time, we designed a sensing platform based on terbium ion (Tb3+) triggered aggregation-induced emission (AIE) of BMNCs. Tb3+ hybrid glutathione (GS) protected Ag/Cu nanoclusters (Tb3+@GS-AgCuNCs) were facilely fabricated according to the complexation reaction between Tb3+ and the carboxyl group of GS. Due to the inner filter effect (IFE), the fluorescence of Tb3+@GS-AgCuNCs decreased significantly in the presence of anticancer drugs with 6-thioguanine and methotrexate as representatives. In addition, the sensing platform was applied to monitor 6-thioguanine and methotrexate in real serum samples, indicating that it has great potential in anticancer drugs related applications.

On the modulation/energy competing of Tb(III)/Eu(III) emission in microporous MOF host for peroxide recognition

Being an important chemical reagent having moderate oxidizability, peracitic acid (PAA) has been applied in modern industries and processing, as well as public safety. These versatile applications make PAA an important analyte to be precisely and sensitively detected. The present work chose the combination of rare-earth-based probe and a microporous host bio-MOF-1 ([Zn8(ad)4(BPDC)6O·2(Me2NH2)+]·G, ad = adenine, BPDC = 4,4′-biphenyl dicarboxylic acid, G = N,N-dimetylformamide and water). Two β-diketone ligands, 1,3-di(pyridin-3-yl)propane-1,3-dione (DPY) and 1,3-diphenylpropane-1,3-dione (DPP), were coordinated to Tb(III) and Eu(III) ions to form probe [RE(DPY/DPP)2]Cl which was loaded into bio-MOF-1 micropores with different loading contents via an ionic exchange operation. The resulting composite samples were fully characterized, including synthesis, morphology, composition, sensing performance and mechanism. The protonation/oxidization of DPY and DPP ligands adjusted their triplet energy level (T1) and consequently affected their energy transfer (ET) efficiency to RE ions, resulting in the variation of RE emission relative intensity. A new pathway for PAA optical sensing was thus proposed. Linear fitting equations were observed for DPY-based samples, showing fluorescence intensity ratio value of 8.80, response time of 9 s, and LOD of 8.08 μM within working region of 0–140 μM.

CO2 Fixation by Dimeric Tb(III) Complexes: Synthesis, Structure, and Magnetism

Two dinuclear complexes, [Tb2(L1)2(piv)2(NO3)2]·H2O (1) and [Tb2(L2)2(CF3CO2)2(H2O)4].2NO3 (2), have been prepared and characterized by single-crystal X-ray diffraction, where each metal ion is doubly phenoxido-bridged by the two phenolato oxygen atoms of the tetradentate Schiff-base ligand. Previous magnetic studies of 1 show that it is not a single-molecule magnet (SMM), while AC magnetic measurements of 2 show that it relaxes quite fast with μSQUID measurements revealing the presence of an interaction operating between the Tb ions. Through DC, μSQUID, and CASSCF calculations, the strength of the interaction in 2 can be quantified, which is of dipolar origin. Both complexes showed efficient catalytic activity toward the carbon dioxide insertion reaction into epoxides for the formation of organic cyclic carbonates. Catalytic synthesis of organic cyclic carbonates smoothly occurred at 60 °C under1 bar carbon dioxide pressure and neat conditions. Exocyclic as well as endocyclic epoxides produced a respective cyclic carbonate product with moderate to high yield (43–100%). Moreover, a high turnover number (7300–10000) along with a high turnover frequency (537.5–5000 h–1) are found in this catalytic reaction.

Single-phase white light material and antibiotic detection of lanthanide metal-organic frameworks.

WLEDs have been widely used in lighting and display equipment due to their energy-saving and environment-friendly advantages, but it is still a great challenge to construct high-quality single-phase white light materials for the preparation of WLEDs. In this work, three Ln-MOFs (HNU-82-84) with the same structure were synthesized by assembling rare earth ions (Tb3+, Eu3+, La3+) and 4,4',4''-nitrilotribenzoic acid (H3TCA) ligands. The structure and optical properties of the three compounds were investigated. Under the ultraviolet lamp, HNU-82-84 displays green light, red light, and blue light emission, respectively. Based on the RGB principle, aiming at the single-phase white material, the proportion of adding rare earth ions is reasonably adjusted to design and synthesize the Ln-MOF (Eu0.015Tb0.037La0.148-TCA) with CIE chromaticity coordinates of (0.319, 0.344). In addition, the WLED was prepared by Eu0.015Tb0.037La0.148-TCA and commercial LED lamps. Furthermore, HNU-82 has strong fluorescence emission and good water stability and can be used to detect nitrofurazone (NZF) and nitrofurantoin (NFT). The concentrations of the aqueous solutions of NZF and NFT had a well correlated linear relationship with the fluorescence quenching effect of HNU-82, and the detection limits were 6.60 × 10-7 mol L-1 and 4.62 × 10-7 mol L-1, respectively. Hence, HNU-82 also has potential as a fluorescent sensor for the detection of NZF and NFT in the aquatic environment.

Single-ion magnet behavior of Ln3+ encapsulated in carbon nanotubes: an ab initio insight.

Single-molecule magnets (SMMs) have attracted large interest owing to their capability to store information at the level of a single molecule, which has great potential for applications in information technology. The key characteristic required for SMM performance is the magnetization blocking barrier, and in the last decade, impressive efforts have been made to increase its height. Herein, we report an ab initio investigation of the SMM behavior of a series of lanthanide ions (Tb3+, Dy3+, Ho3+, Er3+, Tm3+ and Yb3+) encapsulated in zigzag carbon nanotubes (CNTs) of different diameters. The results show that despite the high symmetry of the Ln environment, none of the investigated systems, except for Er3+ encapsulated in the (7,0) CNT, exhibited any blocking behavior. This is mainly attributed to the strong competition between axial and equatorial contributions to the crystal field of these encapsulated ions, resulting in weak or lack of magnetic axiality. The presented results provide useful theoretical guidance for the design of high-performance SMMs via modulating the crystal field of the ligand environment.

Nanosheets of two-dimensional photoluminescent lanthanide phosphonocarboxylate frameworks decorated with free carboxylic groups for latent fingerprint imaging.

The synthesis, structural characterization, exfoliation, and photophysical studies of two-dimensional (2-D) lanthanide phosphonates, named Ln(m-pbc); [Ln(m-Hpbc)(m-H2pbc)(H2O)] (Ln = Eu, Tb; m-pbc = 3-phosphonobenzoic acid) based on the phosphonocarboxylate ligand, are reported. These compounds are neutral polymeric 2D layered structures with pendent uncoordinated carboxylic groups between layers. The nanosheets were obtained by a top-down strategy involving sonication-assisted solution exfoliation and characterized by atomic force microscopy and transmission electron microscropy, showing lateral dimensions from nano- to micro-meter scales, and thicknesses down to several layers. The photoluminescence studies demonstrate that the m-pbc ligand acts as an efficient antenna toward Eu and Tb(III) ions. The emission intensities of dimetallic compounds are clearly enhanced after incorporation of Y(III) ions due to the dilution effect. Ln(m-pbc)s were then applied for labelling latent fingerprints. It is worth noting that the reaction between active carboxylic groups and fingerprint residues benefits the labelling, showing efficient imaging for fingerprints on all kinds of material surfaces.

Toroidal moment and dynamical control in luminescent 1D and 3D terbium calixarene compounds.

A toroidal moment can be generated spontaneously in inorganic (atom-based) ferrotoroidic materials that breaks both time-reversal and space-inversion symmetries, attracting great attention in solid-state chemistry and physics. In the field of molecular magnetism, it can also be achieved in lanthanide (Ln) involved metal-organic complexes usually with a wheel-shaped topological structure. Such complexes are called single-molecule toroics (SMTs), presenting unique advantages in spin chirality qubits and magnetoelectric coupling. However, to date, the synthetic strategies of SMTs have remained elusive, and the covalently bonded three-dimensional (3D) extended SMT has not hitherto been synthesized. Here, two luminescent Tb(iii)-calixarene aggregates with architectures of 1D chain (1) and 3D network (2) both containing the square Tb4 unit have been prepared. Their SMT characteristics deriving from the toroidal arrangement of the local magnetic anisotropy axes of Tb(iii) ions in the Tb4 unit have been investigated experimentally with the support of ab initio calculations. To the best of our knowledge, 2 is the first covalently bonded 3D SMT polymer. Remarkably, solvato-switching of SMT behavior has also been achieved for the first time by desolvation and solvation processes of 1.

Synthesis, characterization and photophysical behaviour of some Tb(III) complexes based on 6,8-dichlorochromone-3-carboxaldehyde as primary ligand

Four green luminescent Tb(III) complexes have been synthesized using a bidentate ligand 6,8-dichlorochromone-3-carboxaldehyde (L) and neutral heterocyclic ancillary ligands. The complexes showed characteristic Tb(III) ion emission bands at 491 nm, 546 nm, 586 nm, and 623 nm, on irradiation with 345 nm. The excellent green luminescence shown by the complexes is due to prominent 5D4→7F5 transition at 546 nm. Three primary ligands and one secondary ligand around the metal ion provide a highly shielded environment, leading to enhanced luminescence properties of synthesized ternary complexes such as quantum yield (ϕTb = 48.76 %); longer lifetime period (τobs = 0.734 ms); intrinsic quantum yield (ηTb = 23.67 %); and radiative rate (KRad = 6.64 × 102 s−1). The ternary complexes deliver higher thermal stability, up to 170 °C.

Optical properties of Ga-Ge-Sb-Se chalcogenide glasses doped with terbium and dysprosium ions, near the fundamental absorption band edge

In the paper, results of measurements of the optical response of chalcogenide glasses of the Ga5Ge20Sb10Se65 composition doped with rare-earth ions Tb3+ or Dy3+, in the wavelength range of 0.7-1.5 μm by the method of IR spectroscopy are presented. Parameters characterizing the fundamental absorption band edge of the glasses --- optical bandgap energy, Urbach tail parameter and weak absorption tail parameter --- have been evaluated. It has been found that doping in low concentrations (up to 0.3 wt%) does not influence the optical bandgap energy and optical properties of the glasses in the range of the Urbach tail, but in the range of the weak absorption tail, optical response of the glasses depends on the activator concentration. Crystallization of the glasses produced by the direct melting method also depends on the activator concentration. In the glasses doped with Dy3+, absorption bands of the ion are located in the range of the weak absorption tail of the glass that makes possible energy transfer between the ions and the gap states of the charge carriers. Keywords: rear earth elements, chalcogenide glasses, bandgap energy, Urbach tail, weak absorption tail, gap states.

Оптические свойства халькогенидных стекол системы Ga-Ge-Sb-Se, легированных ионами тербия и диспрозия, вблизи края полосы фундаментального поглощения

In the paper, results of measurements of the optical response of chalcogenide glasses of the Ga5Ge20Sb10Se65 composition doped with rare-earth ions Tb3+ or Dy3+, in the wavelength range of 0.7 – 1.5 μm by the method of IR spectroscopy are presented. Parameters characterizing the fundamental absorption band edge of the glasses - optical bandgap energy, Urbach tail parameter and weak absorption tail parameter - have been evaluated. It has been found that doping in low concentrations (up to 0.3 mass%) does not influence the optical bandgap energy and optical properties of the glasses in the range of the Urbach tail, but in the range of the weak absorption tail, optical response of the glasses depends on the activator concentration. Crystallization of the glasses produced by the direct melting method also depends on the activator concentration. In the glasses doped with Dy3+, absorption bands of the ion are located in the range of the weak absorption tail of the glass that makes possible energy transfer between the ions and the gap states of the charge carriers.

Energy transfer from self-trapped excitons to rare earth ions in Cs2ZrCl6perovskite variants

A series of Tb3+-doped Cs2ZrCl6perovskite variants are designed based on energy transfer, and the relationships among intrinsic self-trapped excitons, sub-band gap defects and rare earth ions Tb3+were established.

Band Gap Tuning in Transition Metal and Rare-Earth-Ion-Doped TiO2, CeO2, and SnO2 Nanoparticles

The energy gap Eg between the valence and conduction bands is a key characteristic of semiconductors. Semiconductors, such as TiO2, SnO2, and CeO2 have a relatively wide band gap Eg that only allows the material to absorb UV light. Using the s-d microscopic model and the Green's function method, we have shown two possibilities to reduce the band-gap energy Eg-reducing the NP size and/or ion doping with transition metals (Co, Fe, Mn, and Cu) or rare earth (Sm, Tb, and Er) ions. Different strains appear that lead to changes in the exchange-interaction constants, and thus to a decrease in Eg. Moreover, the importance of the s-d interaction, which causes room-temperature ferromagnetism and band-gap energy tuning in dilute magnetic semiconductors, is shown. We tried to clarify some discrepancies in the experimental data.

High Verdet Constant Glass for Magnetic Field Sensors

Due to the high transparency, high Verdet constant, as well as easy processing properties, rare-earth ion-doped glasses have demonstrated great potential in magneto-optical (MO) applications. However, the variation in the valence state of rare-earth ions (Tb3+ to Tb4+) resulted in the decreased effective concentration of the paramagnetic ions and thus degraded MO performance. Here, a strategy was proposed to inhibit the oxidation of Tb3+ into Tb4+ as well as improve the thermal stability by tuning the optical basicity of glass networks. Moreover, the depolymerization of the glass network was modulated to accommodate more Tb ions. Thus, a record high effective concentration (14.19 × 1021/cm3) of Tb ions in glass was achieved, generating a high Verdet constant of 113 rad/(T·m) at 650 nm. Lastly, the first application of MO glass for magnetic field sensors was demonstrated, achieving a sensitivity of 0.139 rad/T. We hope our work provides guidance for the fabrication of MO glass with high performance and thermal stability and could push MO glass one step further for magnetic sensing applications.