Doping Concentration Of Tb3 Research Articles

Preparation of Ba4Lu3F17:Tb3+ fluorescent sensor and its detection for [formula omitted] and 4-NP

Quantitative detection of permanganate (MnO4‐) and 4-nitrophenol (4-NP) is essential for environmental safety. Fluorescence detection technology is one of the most widely used detection technologies, which can be used for the detection of various anions and organic pollutants. In this paper, Ba4Lu3F17:Tb3+ phosphors were successfully obtained by hydrothermal method. The morphology transition of Ba4Lu3F17 crystal from nanoparticles through octahedron to hexagonal prism was realized in the pH range of 3–11. The best luminescent samples were obtained by changing the type of additives and the doping concentration of Tb3+ ions. The obtained Ba4Lu3F17:Tb3+ has high selectivity and anti-interference for MnO4‐ and 4-NP detection, with the detection limits being 0.79 μM and 1.28 μM, respectively.

Bright Transparent Glass‐Ceramic Scintillators With High Fraction (Ca, Sr, Ba)1‐xYxF2+x: Tb Nanocrystals Precipitation for X‐ray Low‐Dose Detection and High‐Resolution Imaging

AbstractTransparent glass‐ceramic (GC) scintillator offers cost‐effective and large‐scale preparation for high‐resolution X‐ray imaging and detectors. However, it remains difficult to precipitate a high fraction of lanthanide activated fluoride nanocrystals that determine scintillation properties in glass. Herein, an ionic‐covalent fluoroaluminate‐phosphate glass network structure is constructed by combining simulation and experimental study, which enables the precipitation of (Ca, Sr, Ba)1‐xYxF2+x: Tb nanocrystals with high crystallinity (30.11%). By adjusting Tb doping concentration, heat treatment temperature and duration, a high internal quantum efficiency of 76.07%, the steady‐state light yield of 12710 photons MeV−1 and the lowest X‐ray detection of 180 nGyair s−1 are obtained. Finally, a high‐resolution (23.4 lp mm−1) X‐ray imaging application is realized by using the (Ca, Sr, Ba)1‐xYxF2+x: Tb GC scintillator. This provides a new option for the development of low‐cost, high‐performance scintillators for X‐ray high‐resolution imaging and low‐dose detection applications.

Up-Conversion Luminescence and Optical Temperature Sensing of Tb3+, Yb3+, Er3+ Doped (Gd, Y, Lu)2O2S Series Phosphors

The phase analysis, luminous intensity, and luminescence lifetime of different doping concentrations of Tb3+ (1 mol %–11 mol %), Yb3+ (9 mol %–54 mol %), Er3+ (0.1 mol %–1.1 mol %) ions and different introduction concentrations of Y3+ (1 mol %–6 mol %) and Lu3+ (0.5 mol %–3 mol %) of Gd2O2S series phosphors were studied systematically. In addition, the energy transfer model of Tb3+-Yb3+-Er3+ was established by analyzing the changes of luminous intensity and luminescence lifetime of novel (Gd, Y, Lu)2O2S phosphors co-doped Tb3+, Yb3+ and Er3+ which were prepared by the coprecipitation-high temperature solid-state reaction method. The luminescence intensity ratio equations of the sample excited by 980 nm was obtained at 313–553 K. And the absolute sensitivities were 0.0033 (313 K). This work is of reference value to the study of the mechanism of up-conversion system.

Dynamic photoluminescent and photochromic properties of CaAl12O19:Eu, Tb: A novel phosphor for advanced dual-modal multicolor anticounterfeiting

The integration of dynamic photoluminescence and photochromism to achieve dual-modal characteristics can substantially elevate the security of anticounterfeiting measures. In this study, a novel bifunctional phosphor, namely CaAl12O19:Eu, Tb possessing dynamic photoluminescence and photochromism, is developed by the sol-gel combustion method. As the duration of exposure to 254 nm ultraviolet radiation increases, the CaAl12O19:Eu, Tb phosphors exhibit exceptional dynamic luminescent characteristics and pronounced color changes. Furthermore, this exposure results in a photochromic phenomenon on the surface of the samples, causing a shift from white to light brown. With an increase in Tb doping concentration, distinct and diverse chromatic variations easily discernible are observed by the naked eye. In addition, the mechanisms underlying the dynamic photoluminescent and photochromic characteristics are analyzed herein. Furthermore, the application of the bifunctional phosphor CaAl12O19:Eu, Tb for advanced dual-modal multicolor anticounterfeiting is explored, offering enhanced security against duplication attempts.

Biocompatible Tb doped Fe3O4 nanoparticles with enhanced heating efficiency for magnetic hyperthermia application

Magnetic hyperthermia has a specific limitation in treating localized and relatively accessible malignant tumors regardless of its promising therapeutic regime. In this present work, Tb doped Fe3O4 magnetic nanoparticles (MNPs) prepared via coprecipitation root and confirmed the structural conformation and phase purity by XRD, FTIR, TEM, and SEM analysis. TGA analysis was carried out for thermal stabilization and to verify the formation of a stable phase. The occupancy of Tb ions at the octahedral sites and cationic distribution can be calculated from Rietveld refinement analysis. The relaxation mechanism, dipolar- dipolar interactions among the particles, and randomly directed magnetic anisotropy axes were investigated by ESR spectroscopy. The magnetic results enumerate that increasing Tb doping concentration leads to increased saturation magnetization and decreased coercivity and retentivity. The self-heating properties of the doped nanoparticles were characterized by measuring specific absorption rate (SAR). The improved saturation magnetization and enriched SAR value enable the doped MNPs for magnetic hyperthermia application with excellent efficacy.

Thermal quenching and evaluation of trapping parameters of thermoluminescence glow-peaks of beta irradiated NaBaBO3: Tb3+ for TLD applications

Here, we report the thermoluminescence (TL) characteristics and trapping parameters under beta ray excitations of pelletized Tb incorporated NaBaBO3 synthesized through the gel combustion method. The chemical composition of this new phosphor was confirmed using X-ray diffraction (XRD). The best doping concentration of Tb was 2 mass%, which results in the highest luminous efficiency. The glow curves of the pellet-formed samples exposed to β irradiation at various doses showed glow peaks at about 188 °C, and 288 °C with a heating rate of 2 °Cs−1. The trapping parameters (E, b, s) related with the prominent the TL glow peaks were determined using Tm-Tstop, initial rise (IR), computerized glow curve deconvolution (CGCD), and variable heating rate (VHR) methods. In the range of 0.1–40 Gy, the total integral values of TL output enlarge linearly with increased dose. The GCD approach was also used to calculate the number of the glow peaks necessary to ensure an appropriate match to the TL response of the phosphor sample and seven TL glow peaks were estimated for all doses (FOM 1.75%), similar to the analysis of Tm-Tstop. The thermal quenching parameters of Tb activated NaBaBO3 for the 1st and 2nd peaks are measured to be W = 0.39 ± 0.04 eV, C = 3.11 × 102, and W = 0.31 ± 0.03 eV, C = 3.11 × 102, respectively. The current results indicate that the NaBaBO3:Tb3+ phosphor is a suitable option in radiation dosimetry for environmental monitoring.

On the structure and ultraviolet emission of terbium doped zinc oxide thin films on silicon after high temperature treatment

Terbium (Tb) doped zinc oxide (ZnO) thin films were deposited on Si substrates by magnetron sputtering in an oxygen containing plasma. The Tb doping concentration was varied from 0 to 0.38 at.%. The effect of heat treatment at high temperature on the ultraviolet (UV) emission was studied along with the structure of the films. Photoluminescence (PL) spectra show that the UV intensity increases much by heat treatment and after 1000 °C annealing the doped films have stronger UV emission than that of an un-doped film. The enhanced UV emission is related to crystallinity improvements of the films. After heat treatment at 1000 °C Zn (Tb) silicates had formed. The film prepared with a Tb concentration of 0.029 at.% showed the best crystallinity and highest UV intensity. Finally, it was shown that the UV PL intensity can be increased further with TiN nanoparticle capping on the surface of the films.

White light emission and fluorescence enhancement of rare earth RE3+ (Tb, Eu, Dy) doped CeF3 nanoparticles

In this study, CeF3: Tb3+, Eu3+, and CeF3: Tb3+, Dy3+ nanoparticles with different Tb3+ ion doping concentrations were synthesized by hydrothermal method. The crystal structure, surface functional groups, fluorescence properties and fluorescence lifetime of nanoparticles were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transforms infrared spectroscopy (FT-IR), and photoluminescence spectroscopy (PL). The results show that the CeF3: Tb3+, Eu3+, and CeF3: Tb3+, Dy3+ nanoparticles synthesized with the doping concentration of Tb3+ at 6 mol% exhibit the best luminescence intensity. The emission spectrum of CeF3: Tb3+, Eu3+ nanoparticles showed typical green light emission and red emission, and the obvious Ce3+→Tb3+→Eu3+ energy transfer process. The emission spectrum of CeF3: Tb3+, Dy3+ nanoparticles showed green light emission, and the Dy3+→Tb3+ energy transfer process. These studies are expected to expand the potential applications of CeF3 in solid-state lighting and fluorescent displays.

Study on the synergistic effect of terbium-doped SnO2 thin film photocatalysts for dye degradation

The undoped and terbium (Tb)-doped SnO2 thin films are coated on the glass substrates using the nebulized spray pyrolysis (NSP) technique. The crystallite size is calculated using the Williamson-Hall method and is found to be decreased from 80 to 56 nm with the increase of Tb doping concentration. Atomic force microscope (AFM) images show the spheroidal shape of the grains. The elemental analysis of the samples was investigated by energy dispersive analysis of X-rays (EDX). An increase in absorbance and decrease in bandgap values provide more photon absorption which enhances the photocatalytic reaction. The PL studies reveal the creation of more defect levels by doping which provides more active sites for catalyzed reactions. The Tb doping with SnO2 improved the rate constant about 0.015/min, and a maximum photocatalytic dye degradation efficiency of 85% against methylene blue dye was observed. Therefore, the fabricated films found potential applications for photocatalysis that enable them to chemical industries.

Improved optoelectronic properties of Terbium co-doped CdO:Zn thin films coated by nebulizer spray pyrolysis method

Abstract Terbium co-doped CdO:Zn thin films have been coated by the facile and an efficient spray pyrolysis technique on the substrate of glass to tune its optical and electrical properties. From XRD analysis, all the diffraction peaks strongly exhibit polycrystalline nature with perfect cubic structure followed by preferential orientation was changed from (111) plane to (200) plane. The nature of the crystal structure and crystallite size is reduced from 20.4 to 16.5 nm by increasing Tb doping concentration due to defects in the lattice. The atomic force microscope AFM mages clearly show that the film's grain size decreases with the Tb dopant. The elements such as Cd, Zn, O, and Tb exists in the elemental mapping and EDS spectra. The transmittance is varied from 70, to 82% at 800 nm, and the maximum bandgap of 3.06 eV is observed for 1.5 wt.% degenerate doping concentration. PL emission at 435 nm shows a high intense peak attribute to the crystalline quality of the film. The electrical property of the film has been greatly improved with doping concentration, which is useful for optoelectronic devices. The TCO based on the 1.5 wt.% Tb co-doped CdO:Zn film shows an improved performance (higher transmission of 82%, lowest resistivity of 7.48 × 10−4 Ω cm, the highest carrier concentration of 11.3×1020 cm−3). These results propose a much simpler route to achieve high-quality Terbium co-doped CdO:Zn thin films for TCO applications.

The Electric and Dielectric Properties of SrF2:Tb3+ Nanocrystals Revealed by AC Impedance Spectroscopy

The electric and dielectric properties of SrF2:Tb3+ nanocrystals were studied by AC impedance spectroscopy. The grain and grain boundary resistances and the complex permittivity with different Tb-doped concentrations were obtained. As the Tb-doping concentration increases, the grain and grain boundary resistances decrease until 6% and then increase. The Tb doping leads to the increase of interstitial F− quantity and the decrease of the activation enthalpy, and finally causes the decreases of grain and grain boundary resistances. When the Tb-doping is larger than 6%, the effect of the deformation potential scattering is dominant, which leads to the increases of grain and grain boundary resistances. The strong dispersion of the permittivity at the low frequencies indicates the carrier was hopping in the transport process. The ε′ and ε″ values at the low frequencies decrease as the sample resistance increases.

Tailoring the properties of nebulizer spray pyrolysis coated FTO thin films through rare earth element terbium for optoelectronic applications

In optoelectronic device, transparent conducting oxide (TCO) acts as an electrode. In this work the rare earth element terbium (Tb) was doped with FTO by simple and inexpensive nebulizer spray pyrolysis (NSP) technique. Structural, optical end electrical properties were investigated for all the synthesized films. X-Ray diffraction (XRD) analysis confirmed that all the prepared films exhibited polycrystalline nature with tetragonal crystal structure and size of the crystalline reduced with increasing Tb concentration. Raman active doubly degenerate mode (Eg), IR active mode (Eu) and vibration mode (B2g) were found from Raman analysis. Atomic force microscope (AFM) images visualises the granular sized particle and the roughness of the Tb doped films. Elememental analysis spectrum exhibited Sn, O, F and Tb elements for 1.5 wt.% Tb doped thin film. Photoluminacence (PL) analysis revealed that UV, blue and green (visible) emission and UV emission intensity was reduced systamatically for the doped films. From UV–Vis analysis, highest optical transmittace were deduced for 1.5 wt.% Tb doped film. Reflectance, absorbance and band gap also been observed for the prepared films. Refractive index, extinction coefficient and dielectric constant values were decreased with increasing Tb doping concentration. High electrical conductivity and carrier concentration were measured using four probe hall effect system. Figure of merit value for the 1.5 wt.% Tb doped film is 1.5 × 10−3 Ω-1 and therefore the prepared film suits to be an electrode in optoelectronic devices.

A GGA+U study of electronic structure and the optical properties of different concentrations Tb doped ZnO

In order to evaluate the electronic structure and optical properties of Tb-doped ZnO with various concentrations of Tb, we used the GGA + U method based on the first-principles method. Our calculations show that the idea of Tb-doped ZnO is feasible. The band gap of Tb-doped ZnO decreases and the Fermi level shifts upward. As the doping concentration increases (3.13%–6.25%), both the absorption peak and reflectance peak of the material decrease, and exhibit a red-shift. In the near-ultraviolet region from 240 to 380 nm, the absorption effect and the reflectivity of Tb-doped ZnO decrease with increasing Tb doping concentration. In the visible region, the absorption effect of Tb-doped ZnO is better than that of pure ZnO, but the reflectance is opposite. Thus, selecting a better doping level can make Tb doped ZnO exhibit better photoelectric properties. The research results can also provide a theoretical reference for subsequent researches of Tb-doped ZnO.

Magnetic characterization of nano-sized terbium doped bismuth ferrite synthesized by sol-gel method

Abstract Bi(1−x)TbxFeO3 (x = 0, 0.03, 0.04, 0.06, 0.09, 0.12) nanoparticles are prepared by sol-gel method. X-ray diffraction analysis shows the formation of perovskite structure in the synthesized samples and crystallite sizes in the range of 15 nm. The perovskite structure together with the presence of a strong absorption peak observed at 545 cm−1 in the Fourier Transform Infrared Spectroscopy measurements, characteristic of FeO6 octahedral, confirms the formation of single phase BiFeO3 structure. The cycloidal spin nature of BiFeO3 is said to be suppressed in particles that are less than 62 nm across enhancing the ferromagnetic signature. The magnetic behaviour of the Bi(1−x)TbxFeO3 nanoparticles is found to change anomalously with change in Tb doping. Vibrating-sample magnetometer studies reveal a maximum in the magnetic moment for a Tb doping concentration of x = 0.03 with clear ferromagnetic order at room temperature. With increase in x beyond 0.03, magnetization decreases, while a further increase beyond x = 0.04 once again increases the magnetization. Room temperature Mossbauer spectroscopy reveals the presence of a paramagnetic doublet and a sextet, the variation of whose relative ratios is in corroboration with the magnetization studies.

Morphology-controlled synthesis and luminescence properties of green-emitting NaGd(WO4)2:Tb3+ phosphors excited by n-UV excitation

Tb3+-doped luminescent materials are widely used as green-emitting materials in the fields of lighting and display. A simple hydrothermal method was used to synthesize NaGd(WO4)2:Tb3+ phosphors without any surfactant or templates. The effects of pH value, reaction time and the doping concentration of Tb3+ on the phase structure, morphology and luminescent properties of the samples were investigated. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrum (EDS), photoluminescence spectra and decay curve were applied to characterize the obtained samples. The results indicate that well-defined uniform square plate-like NaGd(WO4)2:Tb3+ microcrystals can be synthesized at pH 8.0, 453.15 K, reaction time of 20 h. Time-dependent sampling and morphology characterization showed the probable formation mechanism of the square plate-like morphology is: nucleation, dissolution, recrystallization and oriented growth. The main excitation peak at 381 nm corresponding to 7F6→5D3 transition of Tb3+, located in the n-UV region (370–410 nm). Upon excitation with 381 nm, the emission spectrum of NaGd(WO4)2:Tb3+ phosphor showed a typical Tb3+ emission, originated from the 5D4→7FJ (J = 6, 5, 4, 3) transition. The strongest emission peak at 545 nm was attributed to 5D4→7F5 transition, which is located in the green light region. The luminescence intensity for the emissions from 5D4 level increased gradually with the increase of Tb3+ doping concentration and reached a maximum at the doping concentration of 80 mol%, then decreased, implying the occurrence of concentration quenching. The square plate-like NaGd(WO4)2:Tb3+ phosphor achieved the best properties, with the intensive green emission centered at 545 nm under n-UV excitation, indicating that it can be used as green component in n-UV-excited white light emitting diodes.

The effects of Tb doped ZnO nanorod: An EPR study

Abstract Structural and magnetic behaviors were studied and correlated with each other for Zn1−xTbxO nanorods synthesized by hydrothermal method varying x values from 0.01 to 0.05 with 0.01 step increment. The structural properties of Zn1−xTbxO nanorods were determined by X-ray diffraction tool. All nanorods were found as a single phase with ZnO wurtzite hexagonal structure. The concentration-dependent of lattice parameters, cell volumes, microstrain, stress, dislocation density, the locality of the atoms and their displacements, and bond length in Zn1−xTbxO (where x = 0.0, 0.01, 0.02, 0.03, 0.04, and 0.05) structures were detailed. The particles with varying magnifications were observed as random agglomeration using Scanning Electron Microscope measurement tool. ESR spectra of Zn1−xTbxO were collected at room temperature on a Bruker EMX model X-band spectrometer operating at a frequency of 9.71 GHz. ESR measurements have been performed and analyzed through concentration dependence of the g-factor and the line-widths of pike to pike (ΔHPP) of ESR spectra. Experimental and fitting X-band ESR spectra of Tb doped ZnO nanorods with a different doping concentration of Tb recorded at room temperature were presented.

Highly efficient green organic light-emitting devices based on terbium complex by employing hole block material as host

In this work, efficient green electroluminescent (EL) devices with simplified device structure were prepared by doping trivalent terbium complex Tb(PMIP)3 into hole block material TmPyPB. The high triplet energy of TmPyPB helps to confine excitons within light-emitting layer, while the electron transport characteristic of TmPyPB facilitates the balance of carriers on Tb(PMIP)3 molecules. By optimizing the doping concentration of Tb(PMIP)3 and the thickness of each functional layer, highly efficient green EL device with the structure of ITO/MoO3 (3 nm) /TAPC (50 nm) /Tb(PMIP)3 (30 wt%):TmPyPB (25 nm) /TmPyPB (60 nm) /LiF (1 nm) /Al (100 nm) displayed pure Tb3+ characteristic emission with maximum current efficiency, power efficiency and brightness up to 47.24 cd/A (external quantum efficiency (EQE) of 14.4%), 43.63 lm/W and 1694 cd/m2, respectively. At certain brightness of 100 cd/m2, the device still maintained a current efficiency of 19.96 cd/A (EQE=6.1%). Such a device design strategy helps to improve the EL performances of Tb(PMIP)3 and to simplify device fabrication processes, thus reduce the fabrication cost.

Effect of co-doped Tb3+ ions on electroluminescence of ZnO:Eu3+ LED

Rare earth (RE) -doped ZnO electroluminescence is worthy of investigation for phosphor-free white light-emitting diodes (LEDs) due to their pure and sharp emissions. Whereas, the low solubility of RE ions in ZnO films is found to hinder the performance of RE-doped ZnO devices. Herein, ZnO:Eu and ZnO:Eu/Tb LEDs were synthesized and the electroluminescence properties were tested. The results show that the emission intensity of ZnO: Eu/Tb LED is 8 times higher than that of ZnO: Eu LED while the input power is smaller when the concentration of terbium is proper. Furthermore, we discussed the excitation mechanism and found that the ratio of the EL intensity of the 5D1 → 7F1 to 5D0 → 7FJ (J=0 − 4) transition increases with increasing Tb doping concentration, which may indicate the possibility of energy transfer from Tb3+ to Eu3+. The results are believed to be an effective strategy to improve the electroluminescence of RE-doped semiconductor for white LEDs.

Sol-gel derived terbium-containing mesoporous bioactive glasses nanospheres: In vitro hydroxyapatite formation and drug delivery

Terbium (Tb) doped mesoporous bioactive glasses (Tb/MBG) nanospheres were successfully synthesized by a facile sol-gel method using cetyl trimethyl ammonium bromide (CTAB) as the template. Results indicated that Tb/MBG had spherical morphology (100–200nm), higher specific surface area (250–350m2/g) and narrow mesopore size distribution (2–3nm). In order to investigate the effects of Tb on the in vitro bioactivity, prepared Tb/MBG nanospheres were soaking in simulated body fluid (SBF) for 3 days, and results indicated incorporation Tb ions in the MBG nanospheres could improve the hydroxyapatite formation ability. In addition, Tb/MBG nanospheres showed controlled release property of anti-cancer drugs (DOX) and distinct degradation in PBS with different pH values. Their release mechanism can be explained by Fickian diffusion according the Higuchi model, and the delivery of DOX from Tb/MBG nanospheres can be dominated by changing the doping concentration of Tb and the values of pH. In addition, the cytotoxicity of Tb/MBG nanospheres was assessed using a cell counting kit-8 (CCK-8), and results showed that the synthesized Tb/MBG nanospheres at low concentration had no significant cytotoxicity in MC3T3 cells. These all note that this material is a promising candidate for the therapy of bone tissue regeneration.

Single NUV band pumped PbO-GeO 2 -TeO 2 :Tb 3+ yellowish green emitting glass material for tricolor white LEDs

Abstract In this work, Tb 3+ ions doped lead-germanate-tellurite (LGT) glasses were prepared by conventional melt quenching technique with different dopant concentrations ranging from 0.5 to 3.5 mol %. X-ray diffraction (XRD) and FT-IR analysis were carried out to analyze the structural properties of LGT glass. The excitation spectra revealed a single band centered in the NUV region at 380 nm by monitoring emission at 545 nm. The emission spectra consist of four bands, which are attributed to the 5 D 4 → 7 F J (J = 3–6) transitions. Among these transitions, the strong emission band was observed at 545 nm corresponding to the 5 D 4 → 7 F 5 transition and the optimized doping concentration of Tb 3+ ions was 2 mol %. The Huang's theory and I-H model indicate the possibility of energy transfer via electric dipole-dipole interaction between Tb 3+ ions. The CIE chromaticity coordinates were ( x = 0.282 and y = 0.614) and emits intense yellowish green light. The decay curves measured for 5 D 4 level for the samples with different doping concentrations and the lifetime for the optimized sample was 548 μs. The results indicate that these glasses have potential applications in solid state lighting and display devices.