Concentration Of Neodymium Ions Research Articles

Hybrid upconverting/paramagnetic Fe3O4/Gd2O3:Er3+, Yb3+, Mg2+, Nd3+ nanoparticles – synthesis, characterisation and biological applications

The goals of this work are to design and develop a technology for fabrication and study of multifunctional properties of core/shell nanoparticles (NPs) as magnetic/luminescent markers. The new hybrid core/shell Fe3O4/Gd2O3:1% Er3+, 18% Yb3+, 2.5% Mg2+, x% Nd3+ NPs doped with different concentrations of neodymium ions, where x = 0%, 0.5%, 0.75%, 1%, 2%, 4%, were synthesized by the co-precipitation method. The NPs were characterised using XRD, TEM, SEM, EDX, confocal microscopy and photoluminescence. Fe3O4 (core) consists of several 13 nm NPs. The core/shell NPs have sizes from 220 nm to 641 nm. In this latter case, the shell thicknesses were 72, 80, and 121 nm. The upconversion efficiency properties and magnetic properties of the hybrid NPs were investigated. In the core/shell NPs, the addition of Nd3+ quenches the luminescence. The magnetic response of core/shell samples is rather paramagnetic and does not differ significantly from that registered for the shell material alone. For Gd2O3:1% Er3+, 18% Yb3+ and Fe3O4/Gd2O3:1% Er3+, 18% Yb3+, 2.5% Mg2+, 0.5% Nd3+, at 300 K, the values of the magnetization registered at ~ 40 kOe are similar and equal to ~ 5.3 emu·g−1. The survivability of the HeLa tumor cells with the presence of the core/shell NPs was investigated for 24 h. The NPs are non-toxic up to a concentration of 1000 µg·ml−1 and penetrate cells in the process of endocytosis which has been confirmed by confocal microscope studies.

Optical and luminescence studies of Nd3+ doped phosphate glasses for pulsed laser applications

A series of glass with appropriate chemical compositions (60-x) P2O5 + 20 Bi2O3 + 10 SrF2 + 10 Na2 CO3 + x Nd2O3, (x = 0.1, 0.5, 1.0, 1.5, and 2.0% by mole) were prepared by using the melt quenching technique. The glass phase structure was confirmed by using X-ray diffraction technique. The structural analysis using FTIR technique it reveals characteristic bonding vibrations and different functional group in the glass matrix. The elements present in the fabricated glass sample was analyzed by using EADX spectrum. J-O intensity parameters Ω2, Ω4, and Ω6for the currently being researched PBNSNd10 glass have values of 9.80 × 10-20 cm2, 3.305 × 10-20 cm2, and 5.576 × 10-20 cm2 sequentially. The J-O parameters shows a trend of Ω2 > Ω6 > Ω4. The near infrared emission spectra recorded with 808 nm laser diode excitation for various concentrations of neodymium ions show the emission intensity is highest for the 4F3/2 → 4I11/2 transition at 1056 nm. The measured decay times 4F3/2 level decreased with increasing Nd2O3 ions because of concentration quenching effect. The obtained results in present study have been compared with previous results obtained for Nd2O3 doped glasses.

Modeling and Numerical Simulation of the Gain Spectrum of 1250nm-1350nm Neodymium-doped Broadband Fibre Amplifiers

Nowadays, with the rapid development of information technology, the optical transmission of signals has replaced electrical transmission and become the most widely used method in the world. However, when transmitting the light signal, the loss in energy could not be ignored in the long distance transmission, which highlights the importance of fibre amplifiers. This research focuses on studying the Neodymium-doped fibre amplifier operating in the 1250nm-1350nm band. In this paper, the rate equation and power propagation equation of Neodymium ions are modeled using MATLAB based on its four-level system. With that model, the variations of the gain of the Neodymium-doped fibre amplifier with fibre length, the concentration of Neodymium ions and pumping power are simulated. The results demonstrate that as the fibre length increases in the certain range, the gain rises at first and then drops. The presented peak could be easily obtained. The changing trend of the gain when the concentration of Neodymium ions increases is similar. However, the gain continues to increase when the pump power increases in the practical range. This experiment provides great references in the production of the Neodymium-doped fibre amplifier in the future.

Extensive study on the optical and structural characteristics of Nd3+ doped Lead-Borate-Strontium-Tungsten glass system: Judd–Ofelt analysis

In this paper, a neodymium doped Lead-Borate-Strontium-Tungsten glass system is synthesized by melt - quenching method. The samples are fabricated according to the composition 45B2O3-45PbO-7SrO-(3-x)WO3-(x)Nd2O3, where x = 0, 1, 1.5, 2 and 2.5 mol%. As the neodymium ion concentration is increased, the measured density and molar volume of the glass is observed to increase. Raman spectroscopy and FTIR measurements were conducted to study the structure of the glass system and examine modifications that occurred by adding various Nd3+ ion concentrations. FTIR and Raman analysis revealed vibration and bonds stretching of various borate groups. UV–Vis–NIR spectroscopic measurement displays 6 absorption bands and was used to evaluate refractive indices, optical bandgap energies and other associated parameters. The J–O intensity parameters of Nd3+ions are evaluated. The obtained intensity parameters exhibited a trend which follows Ω2 > Ω4 > Ω6 for all samples. Additionally, the experimental and theoretical oscillator strengths of the radiative 4f transitions, refractive indices(n), branching ratio(β) and lifetimes(τ) were determined. The spectroscopic quality factor obtained suggests the suitability for the glass system to be used in photonic applications.

Comprehensive study of spectroscopic and holographic properties of the chlorine-containing photo-thermo-refractive glass doped with neodymium ions

A study of the optical, spectral-luminescent and holographic properties of the chlorine-containing photo-thermo-refractive (PTR) glass doped with neodymium ions was carried out. The chlorine-containing PTR glass has been recently produced by replacing the bromine in the standard PTR glass with chlorine. The glass was doped with different concentrations of neodymium ions. The spectroscopic analysis of neodymium in the glass has been performed using the Judd-Ofelt theory based on experimental absorption and emission measurements. Spectroscopic parameters, such as the Judd-Ofelt intensity parameters, radiative and non-radiative transition probabilities, fluorescence lifetimes, stimulated emission cross-sections, and branching ratios, were obtained and found to be comparable with the parameters of the standard PTR glass doped with neodymium. The mechanism of non-radiative energy transfer was analyzed based on the lifetime kinetics measurements. It was found that cross-relaxation among neodymium ions is the dominant non-radiative energy transfer mechanism.Holographic characteristics of the chlorine-containing PTR glasses doped with neodymium have been also studied. The volume Bragg grating was recorded in the doped and undoped glasses. It was found that the UV exposure and heat treatment do not change the spectroscopic characteristics of neodymium ions in the glasses, while the neodymium ions reduce the sensitivity of the glass. The energy transfer from cerium to neodymium when irradiating using the 325-nm laser makes the hologram recording possible on the samples of low neodymium concentrations only. Studying the spectroscopic and holographic properties of the chlorine-containing PTR glass doped with neodymium ions demonstrates the potential of using such a material in the applications of photonics integration and monolithic optical devices like distributed-feedback lasers.

Dopant segregation in YAG single crystal fibers grown by the laser heated pedestal growth technique

In this study, we report self-segregation of dopants in a crystal matrix within a single crystal (SC) fiber. Neodymium and holmium-doped yttrium aluminum garnet (YAG) fibers were grown using the Laser Heated Pedestal Growth (LHPG) technique and cross-sectional dopant concentration was measured using electron-probe micro-analysis. It was observed that the degree of auto-segregation of the rare-earth dopant depended on the difference in ionic size of the dopant ion and the Y3+ ion in the YAG matrix. While holmium showed little tendency to self-segregate, the concentration of neodymium ions varied as much as 25% across the cross-section of the fiber. Strong correlation between the dopant concentration profile and fiber draw speed was also demonstrated. Since the local refractive index depends on the concentration of dopants, a refractive index profile can be achieved by a dopant profile across the fiber cross-section. Engineered index profiles can be realized by varying growth conditions, dopants, crystal matrix, etc. Such an approach is promising in applications such as the development of monolithic SC fibers with graded-index profiles.

Study of the luminescence of calcium niobate activated by neodymium

In this study, samples of calcium niobate activated with neodymium (CaNb2O6:Nd) were synthesized using the solid-phase method in air. The optical properties were investigated at 300 K. The optical bandgap of CaNb2O6:Nd was found to be 3.6 eV. The luminescent properties of the samples in the infrared spectral region were analyzed, and the optimal concentration of neodymium ions in the compound was determined. The luminescence spectrum consists of a set of bands with the maxima located at wavelengths of 896, 1061, and 1341 nm. The luminescence decay kinetics is characteristic of intracenter luminescence. The average lifetime of Nd-ion excited states in a CaNb2O6:Nd compound is within the range of 40–100 µs depending on the activator concentration.

Optical traits of neodymium-doped new types of borate glasses: Judd-Ofelt analysis

Improvement in the optical properties of rare earth ions activated inorganic glasses is one of the challenges in materials science. Driven by this idea a new series of borate glass activated with varying concentrations of neodymium ions (Nd3+) were prepared using the melt-quenching technique. Such glasses were characterized by various analytical tools to determine the Nd3+ contents dependent spectroscopic attributes. Furthermore, Judd-Ofelt intensity parameters of Nd3+ were evaluated. XRD pattern of as-quenched samples confirmed their amorphous nature. FTIR spectra of glasses revealed the bonds stretching and vibration of different borate functional groups. UV–vis spectra of glasses displayed twelve absorption bands accompanied by hypersensitive transition positioned at 581 nm which were used to calculate the oscillator strengths. Judd-Ofelt parameters for all glasses disclosed a similar trend of Ω4 > Ω6 > Ω2. Proposed glass hosts were found to be effective for the enhancement of spectroscopic quality factor of Nd3+ as much as 1.2603, suggesting their usefulness in photonics devices.

A New Highly Selective Neodymium(III) Polyvinylchloride Membrane Electrode Based on 4-Hydroxypyrrolidine-2-Carboxylic Acid as an Active Material

The present paper describes the fabrication of a new polyvinylchloride (PVC) membrane electrode for the determination of Nd(III) ion based on 4-hydroxypyrrolidine-2-carboxylic acid (LHP) as an active material along with sodium tetraphenyl borate (NaTPB) as an anionic additive and acetophenone (AP) as solvent mediator. The optimum composition (%, w/w) of the best performing membrane contained 66 AP, 30 PVC, 2 NaTPB and 3 LHP. The basic analytical parameters of this electrode such as slope characteristics, detection limit, response time, selectivity and pH effect were assessed. The electrode displayed a Nernstian response in terms of slope (20.5 ± 0.4 mV per decade) and response time (~8 ± 1 s) over a wide neodymium ion concentration range of 10–6 to 10–2 M with a detection limit of 7.5 × 10−7 M. The potentiometric response of the electrode was constant in the pH range of 3.2‒8.9. According to the selectivity coefficients determined by the matched potential method, the interference of many common alkaline, alkaline earth, transition, heavy metals and specially lanthanide ions in determination of Nd(III) ion was very low. The proposed electrode has been successfully used as an indicator electrode in the potentiometric titration of Nd(III) ion with EDTA and applied for determination of Nd(III) ion in mixtures of different ions.

Reactive sintering of highly-doped YAG/Nd3+:YAG/YAG composite ceramics

Multilayer YAG/Nd3+:YAG/YAG composite laser ceramics were obtained by the reactive sintering in vacuum. The effect of the neodymium ion concentration (1-4 at.%) on the formation of defects and optical quality of composite ceramics was studied. It was found that neodymium ions modify densification kinetics during solid-state reactive sintering of the highly-doped Nd3+:YAG ceramics by decreasing shrinkage rate in the temperature range 1320-1350 ?C. Differences in phase transformation kinetics during reactive sintering lead to generation of pores at the interface of adjacent layers which decrease the optical homogeneity of fabricated YAG/Nd3+:YAG/YAG composite ceramics. The influence of layered structure on the laser performance of optical ceramics was investigated. It was shown that the ceramics with multilayer composite architecture have slope efficiency almost twice as the single-layer ceramics with the same composition (22% and 12.5%, respectively).

Effect of Paramagnetic Metal Ions on 1H Diffusion in Trihexyltetradecylphosphonium Benzoate Ionic Liquid

Introduction The high thermal stability of ionic liquids has been exploited to be used in diverse applications (e.g., energy storage devices, extraction, lubrication etc.) [1-4]. The physicochemical properties (mobility, diffusion) of ionic liquids changes when used in a wide temperature range. Several methods are available to study the diffusion and mobility of ionic liquids, of all NMR is most accurate and reliable technique to study the translational (diffusion) and rotational motions in ionic liquids [5]. Pulsed field gradient spin echo and stimulated NMR has been utilized to study the diffusion process in ionic liquids [6-7]. Studies on the diffusion process in phosphonium based ionic liquids are scarce [8]. Moreover the effects of paramagnetic metal ion on the diffusion in ionic liquid are few. In this context we studied the effect of paramagnetic metal ion (neodymium) on the translational motion (diffusion) of Trihexyl-tetradecyl-phosphonium benzoate (P66614 TTPB) ionic liquid using pulsed field gradient NMR. Experimental Method TTPB (C39H73O2P) (KOEI chemicals Ltd., Japan, >98.0%) was used as received. Neodymium chloride (NdCl3, Wako Pure Chemical Industries, Japan) was dissolved in de ionized millipore water. The aqueous solutions were filtered using a 25 µm sieve to avoid precipitation. To start with, 0.5 ml aqueous NdCl3 is added to 1gm of TTPB and the mixture was shaken well for 60 min using a shaker followed by centrifugation for 60 min at 1000 rpm. The concentration of metal ion was measured by ICP-AES (Optima 3300XL, Perkin-Elmer, USA). 0.3 ml of neodymium containing TTPB is added to a 5 mm NMR glass tubes for 1H and NMR measurements. JEOL ECA 300 FT-NMR spectrometer operating at a frequency of 300.5 MHz for 1H nuclei was used to study the 1H diffusion. Results and Discussion Neodymium ion concentration in the TTPB ionic liquid was evaluated using ICP-AES and found to be in the range 0.02 mmol/L to 1.2 mmol/L. A small amount of water is found to be incorporated into the ionic liquid along with neodymium ions. Downfield shifts are observed in the 1H 1D NMR spectra with increasing neodymium concentration. 1H diffusion coefficients of the cation and anion were measured in the temperature range 24 - 80 °C. The temperature dependence of diffusion coefficient for different neodymium concentrations are shown in Fig. 1. As observed from Fig. 1 a, at low concentrations (0.02 ~ 0.1 mmol) the diffusion coefficient is in this order DH2O > Danion > Dcation. At higher concentrations (0.4 ~ 1.2 mmol) the diffusion coefficient of the cation and anion are almost the same as observed from Fig. 1 (DH2O ~ Danion ~ Dcation). Conclusion The presence of a paramagnetic ion (neodymium) in the ionic liquid shifts the proton chemical shift to lower field, due to its high magnetic dipole moment. From the diffusion results, 1H diffusion coefficient of the anion is higher than the cation at low concentration of neodymium. The anionic diffusion coefficient decreases with increasing neodymium concentration and converges with the cationic diffusion coefficient. This is possibly due to the formation of clusters around the neodymium ion at high concentrations. References E.Binetti, A.Panniello, L.Triggiani, R.Tommasi, A.Agostiano, M. L. Curri and M. Striccoli, J. Phys. Chem. B, 2012, 116, 3512.R. Atkin and G. G. Warr, J. Phys. Chem. C, 2007, 111, 5162.H. Tokuda, K. Hayamizu, K. Ishii, M. A. B. H. Susan and M. Watanabe, J. Phys. Chem. B, 2005, 109, 6103.F. U. Shah, S. Glavatskih, P. M. Dean, D. R. MacFarlane, M. Forsyth and O. N. Antzutkin, J. Mater. Chem., 2012, 22, 6928–6938.W. Price, NMR studies of translational motion, Cambridge University Press, 2009, p. 393.K. Hayamizu, S. Tsuzuki, S. Seki and Y. Umebayashi, J. Chem. Phys., 2011, 135, 084505.K. Hayamizu, S. Tsuzuki, S. Seki and Y. Umebayashi, J. Phys. Chem. B, 2012, 116, 11284–11291.Andrei Filippov, Faiz Ullah Shah, Mamoun Taher, Sergei Glavatskih and Oleg N. Antzutkin, Chem. Phys. Phys. Chem., 2013, 15, 9281. Figure 1

Broadening of paramagnetic resonance lines by charged point defects in neodymium-doped scheelites

We study paramagnetic resonance linewidth in a series of CaWO4 and CaMoO4 crystals with different concentrations of neodymium ions (0.0031–0.81 at %). Experimental data are interpreted in the framework of the statistical theory of line broadening by charged point defects. In our calculations, three different contributions are singled out: arising from the local electric fields, electric field gradients and magnetic fields of the nearby point defects. The interaction parameters are determined from the spectroscopic data available for Nd:CaWO4 crystal. Direct calculations of the linewidth are performed for different crystal orientations with respect to external magnetic field. We conclude that major contribution to the broadening comes from the interactions with random electric fields produced by neodymium and charge compensator ions.

Synthesis of neodymium doped yttria nanopowders by microwave-assisted glycine combustion method and the powder characteristics

Trivalent neodymium ion doped yttria (Nd3+:Y2O3) nanopowders were synthesized by using a glycine combustion method. The characteristics of the Nd3+:Y2O3 nanopowders with different calcination temperatures and Nd3+ ion doping concentrations were analyzed to determine the optimum synthesis conditions of the samples. Thermo-gravimetry and differential scanning colorimetry (TG/DSC), XRD and FTIR analysis showed that the novel glycine-gel microwave combustion method can provide an effective reaction to form yttria nanopowders. The peak positions of the emission spectra of Nd3+ ion in yttria host did not differ with the neodymium ion concentration or the calcination temperatures, whereas the luminescence intensities were heavily dependent on the ion concentration and calcination temperatures.

Spectroscopic properties of Nd 3+ ions in nano-perovskite CaTiO 3

In this work, we present for the first time the spectroscopic properties of perovskite nanocrystals CaTiO 3: Nd 3+, measured at room and liquid nitrogen temperature. Samples were prepared by the sol–gel method and annealed at 700 and 1000 °C. The concentration of Nd 3+ ranged from 0.5% to 5%. Average nanocrystallite size primarily depends on the annealed temperature and is about 25 and 50 nm for 700 and 1000 °C, respectively. The absorption, emission and excitation spectra (monitored at 1078 nm) as well as the decay time profile of the emission from the 4 F 3/2 energy level of Nd 3+ are obtained. The increasing amount of Nd 3+ ions decreases the lifetime of the 4 F 3/2 level and that changes from 146 μs for 0.5% to 50 μs for 5% of Nd 3+ concentration. The strongest emission was observed at two regions: 1050–1120 nm and 865–930 nm and was assigned to the 4 F 3/2→ 4 I 11/2 and 4 F 3/2→ 4 I 9/2 transitions, respectively. The spectroscopic quality parameter of neodymium in the CaTiO 3 lattice has been calculated from the emission spectra. The influence of luminescent properties depending on the annealing temperature and concentration of neodymium ions is discussed.

Photocatalytic degradation of Rhodamine B under visible light with Nd-doped titanium dioxide films

Microporous titanium dioxide films were prepared by the sol-gel methods on glass substrates, using tetrabutyl titanate as source material. In order to absorb the visible light and increase the photocatalytic activities, different concentrations of neodymium ions (Nd/Ti molar ratio was 0.5%, 0.7%, 0.9%, and 1.1% respectively) were added into the sol. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and atom force microscopy (AFM) were applied to characterize the modified films. A kind of typical textile industry pollutant (Rhodamine B) was used to evaluate the photocatalytic activities of the films under visible light. The results showed that the activities of the films were improved by doping Nd ions into the sol.

Synthesis and photoluminescent properties of neodymium-ion doped perovskite oxides

The visible transitions of Nd 3+ ions were found in the Nd x (Ca 1− x− y− z ,Ba y ,Sr z) TiO 3 system. All the compositions exhibit a pseudo-cubic structure. Based on the diffused reflectance spectra, the valence-to-conduction band edge for this system appears at 335 nm. A bright red luminescence at 613 nm is formed under excitation at 335 nm for all the compositions with x = 0.002 – 0.005 . With an increase in the dopant concentration of neodymium ions, the excitation and emission intensities both increase up to x = 0.005 of neodymium substitution. There is no shift in the excitation and emission spectra of the samples. This report is believed to be the first one in the literature to demonstrate strong visible emission from neodymium-doped oxide systems.

Spectroscopic and magnetic behavior of xNd2O3(1$minus;x)(3Bi2O3aPbO) glasses

Glasses of the x Nd 2 O 3 (1− x )(3Bi 2 O 3 · PbO) system with 0⩽ x ⩽0.30 were obtained and studied by IR spectroscopy, X-ray photoelectron spectroscopy (XPS), density and magnetic susceptibility measurements. IR and density measurements show that the addition of neodymium ions produces structural changes and the neodymium ions play a network modifier role in the host glass matrix. XPS investigation permitted following the evolution of the structural disorder, of the degree of polymerization of bismuthate chains and of the fraction of bridging oxygens with respect to the neodymium ion concentration of the studied glasses. Magnetic susceptibility data show that the Nd 3+ ions are present as isolated species for x ⩽0.05 and as both isolated and exchange coupled species for higher x values.

Spectroscopic and magnetic behavior of xNd 2O 3(1− x)(3Bi 2O 3 · PbO) glasses

Glasses of the xNd 2O 3(1− x)(3Bi 2O 3 · PbO) system with 0⩽ x⩽0.30 were obtained and studied by IR spectroscopy, X-ray photoelectron spectroscopy (XPS), density and magnetic susceptibility measurements. IR and density measurements show that the addition of neodymium ions produces structural changes and the neodymium ions play a network modifier role in the host glass matrix. XPS investigation permitted following the evolution of the structural disorder, of the degree of polymerization of bismuthate chains and of the fraction of bridging oxygens with respect to the neodymium ion concentration of the studied glasses. Magnetic susceptibility data show that the Nd 3+ ions are present as isolated species for x⩽0.05 and as both isolated and exchange coupled species for higher x values.

Single-mode direct-ultraviolet-written channel waveguide laser in neodymium-doped silica on silicon.

A waveguide laser with a neodymium-doped silica core is fabricated on a silicon substrate by a combination of flame hydrolysis deposition, solution doping, and direct UV writing. The neodymium-ion concentration is estimated to be approximately 8000 parts in 10(5). The propagation loss around 1.05 microns is < 0.8 dB/cm. Lasing in the range 1048-1056 nm and 1356 +/- 1 nm is observed. A slope efficiency of 33% for a high-reflectivity output coupler and a threshold of 4 mW of absorbed power for a 25% output coupler are measured for the 4F3/2-->4I11/2 transition.

Large disc-shaped active elements made from neodymium phosphate glass elements made from neodymium phosphate glass

A technology has been developed for the production of large active elements made from KGSS 0180/35 neodymium phosphate glass (with a neodymium ion concentration of NNd53.5 x1020cm-3), iintended for powerful pulsed lasers with high output radiation energy. The neodymium glasses were melted using a two-stage or single-stage process with high-purity reagents in crucibles made from dispersion-strengthened platinum or a newly developed highstrength cristobalite refractory, which, along with other process methods, makes it possible to obtain glass that contains no metallic platinum inclusions. The main elements of the process for synthesizing neodymium glass are deep oxidation of the melt with dry oxygen in order to convert traces of platinum and iron to higher valence states and simultaneously eliminate hydroxyl group impurities, as well as the use of a nonplatinum refractory to fabricate the glassware. The resulting glasses are characterized by high optical homogeneity, high luminescence lifetime of the neodymium ( t~300 us), radiation strength to 33 J/cm2 when the exciting pulse width is 3?4 ns, and a nonactive absorption coefficient at the lasing wavelength of about 0.0015 cm-1. The required high-quality surface processing of the active elements is provided by fine annealing of the blanks and by using grinding?polishing equipment with program control.