Dysprosium Ions Research Articles

Influence of the synthesis pathway upon the thermoluminescent response of gadolinium aluminate matrix phosphors

The phosphors endowed with a glow curve have a peak much more intense than the others, sensitization to low doses, and a linear relationship between the thermoluminescent response and the dose, which are in demand in the dosimetry market. The gadolinium aluminate has been successfully used as a host lattice of phosphors with luminescent properties. Principally, the luminescent response of the said matrix has been improved by doping with rare earth ions. The thermoluminescent signal depends on the synthesis route because the defect density of a crystal is closely connected to the production pathway that the material went through. Therefore, a crucial step in sensitizing a phosphor is selecting a synthesis route that enhances the efficiency of its thermoluminescent mechanisms. The research herein focused on synthesizing phosphors composed of gadolinium aluminate with no dopant and doped with two molar percent of dysprosium, using two different routes. Among the two synthesis pathways, it was determined to be the most suitable for enhancing the thermoluminescent response of the aforementioned phosphors. The methods employed were reverse coprecipitation and the modified citrate precursor. The phosphors obtained by the reverse coprecipitation method showed the most sensitive thermoluminescent signal. Mainly, the phosphor activated with the dysprosium ion produced the most intense signal, suggesting an improvement in the thermoluminescent mechanisms due to the dopant insertion.

Microwave-assisted combustion synthesis and characterization studies of novel dysprosium doped yttrium calcium borate (Dy3+: Y2CaB10O19) phosphor materials for efficient white light applications

Micro-wave assisted combustion synthesis technique was adopted to synthesize the dysprosium-doped yttrium calcium borate xDy3+: Y(2-x) CaB10O19 (Dy:YCB) polycrystalline phosphor materials with varying concentrations (x = 1, 3, 5, 7 and 9 mol %) for the first time. The formation of phase, crystal structure was analyzed by x-ray diffraction study and was affirmed to be formed pertaining to the monoclinic crystal structure (a = 11.475 Å, b = 6.345 Å, c = 9.223 Å and α = γ = 90°, β = 91.83°) with C2 space group. The absorption capability of the prepared samples was investigated by UV-DRS spectroscopy and the optical band gap was found to be 5.28 eV. FTIR study validated the presence of functional groups and their molecular vibrations. The excitation wavelength of the synthesized samples was found to be 350 nm from photoluminescence excitation (PLE) spectra. The PL emission spectra were recorded to authenticate the emission wavelengths and found to possess two emission peaks at 480 nm (blue) and 577 nm (yellow) contributed by the Dy3+ ions. The optimized dopant concentration of dysprosium ion was fixed at x = 0.07 to avoid the concentration quenching effect. The chromaticity co-ordinate of optimized sample was determined to be x = 0.3188, y = 0.3233 which are closer to ideal white light co-ordinate. The color temperature was determined to be 6209 K, which occurs in the cool white light region. Luminous efficacy of radiation (LER) was determined to be 269.31 l m/Wopt for the optimal phosphor. The luminous efficiency for the optimal phosphor was determined to be 40%. Color rendering index (CRI) of the optimal sample was evaluated to be 77. Internal quantum yield (IQE) of the optimal sample was determined to be 50.58 %. The phosphor materials have excellent thermal stability as validated from the temperature dependent PL measurements.

Magnetocaloric effect modeling of dysprosium-transition metal based intermetallic alloys for magnetic refrigeration application using hybrid genetic algorithm based support vector regression intelligent method.

Intermetallic alloy containing rare earth dysprosium ions with the associated unfilled 4f shell electrons and sub-lattice of 3d-transition metal, results into fascinating magnetic properties which are useful for green refrigeration technological application. Magnetocaloric effect remains the fundamental principle upon which magnetic refrigeration technology is based while this cooling technology has advantages of cost effectiveness, high efficiency and environmental friendliness as compared with the existing conventional gas compression systems. Maximum magnetic entropy change (which controls the hugeness of magnetocaloric effect) of intermetallic alloy Dy-T-X (where T = transition metal and X = any other metal or nonmetal) is modeled in this work using hybrid genetic algorithm based support vector regression (GSVR) computational intelligent method with applied magnetic field, ionic concentration and ionic radii descriptors. The developed GSVR-G model with kernel Gaussian function outperforms GSVR-P model with polynomial function with improvement of 85.23%, 78.82% and 78.67% on the basis of the computed correlation coefficient (CC), mean absolute error (MAE) and root mean square error (RMSE) on testing sample, respectively. The developed model further investigates the influence of applied external magnetic field on magnetocaloric effect of DyCuAl intermetallic alloy. The developed models in this work circumvent experimental challenges of magnetocaloric effect determination while the recorded precision of the developed model further opens doors for possible exploration of these intermetallic compounds for addressing environmental challenges associated with the present system of cooling.

Sorption Behaviors of Amorphous Titanium Phosphate Towards Neodymium and Dysprosium

Due to the limited supply of critical metals, their recovery from alternative sources has become a very important issue. In particular, end-of-life magnets contain significant amounts of neodymium (Nd) and dysprosium (Dy) ions and are considered secondary sources. The present study focused on the sorption and separation performance of titanium phosphate for Nd and Dy ions in an aqueous solution. In this regard, amorphous titanium phosphate (am‐TiP) was prepared via one‐step precipitation. XRD, SEM‐EDS, FTIR, and BET analysis were utilized to enlighten the morphological, structural, and surface properties of am‐TiP. The uptake of Nd3+ and Dy3+ ions was examined individually and in multiple element solutions depending on solution pH, contact time, metal concentration, and the presence of Co2+ ions. The maximum uptake capacity was 40.16 mg/g at pH 6 for Nd3+ and 26.95 mg/g at pH 4 for Dy3+. Am‐TiP has been observed to exhibit selectivity towards Nd3+ and Dy3+ ions in solutions containing Co2+ ions. The highest desorption yields obtained for Nd3+ and Dy3+ using 1.0 mol/L HCl were 95.2% and 97.4%, respectively.

Theoretical Calculations and Experimental Investigation of Separation of Dy3+, Er3+, Tm3+ and Yb3+ by Cascade Extraction in TOGDA–Kerosene/Hydrochloric Acid System

The hot spot extraction agent N,N,N′,N′-tetraoctyl-3-oxoglutaramide (TODGA) has the advantages of novelty, high efficiency and environmental protection in the separation of rare earths by tandem extraction. In this paper, the characteristic parameters for the separation of dysprosium, erbium, thulium and ytterbium ions in the TOGDA–kerosene/hydrochloric acid system for tandem extraction were calculated. Using a 10% TODGA–kerosene/5 mol·L−1 hydrochloric acid extraction system, the mixture containing Dy3+ 0.258 mol·L−1, Er3+ 0.252 mol·L−1, Tm3+ 0.248 mol·L−1 and Yb3+ 0.242 mol·L−1 can be separated by three separation steps, and four products of Dy3+, Er3+, Tm3+ and Yb3+ can be obtained. The purity of the four products was 99.80%, 99.20%, 99.70% and 99.70%, and the yields were 99.03%, 98.97%, 97.88% and 96.98%, in order. In this paper, the reasons were analyzed for the differences in the ability of the TODGA system to extract heavy rare earth ions (REEs) in terms of density functionality, complex structure and bond valence model. These will provide more basic data and guidance for the industrial application of TODGA.

Dy3+ and Sm3+ ratio variation effects on electrical properties of lithium fluoride bismuth borate glass system

Since less attention was paid to study of electric properties of glasses doped with RE ions, in present work conductivity (AC and DC) and dielectric properties of Dysprosium (Dy3+) and Samarium (Sm3+) ion co-doped 60B2O3•30LiF•10Bi2O3 glasses were examined. Conventional melt quench method was used to synthesize the amorphous glass samples. It was observed that dc conductivity obeyed the Arrhenius law and the ac conductivity followed Jonscher's Power Law. The Conductivity mechanism was investigated on the basis of the trend followed by frequency exponent “s” parameter and all the compositions satisfied the Overlapping large polaron tunnelling (OLPT) model. Dielectric properties: Dielectric Constant (ε′), Dielectric loss (ε'′) and tangent loss (tanδ) were also investigated and observed to decrease with frequency and finally attained a minimum constant value at higher frequencies. The high rate of change in dielectric properties at low frequencies was attributed to space charge polarization while at higher frequencies it was decreased due to inertia of ions. Cole-Cole plots encompasses depressed semicircular arcs which evidenced the presence of constant phase element and non-Debye relaxation behaviour.

Cool white light generation of Dy3+ activated aluminum sodium calcium borate glass for W-LED application

The Dy3+-activated aluminum sodium calcium borate glass with white light emission might have been created through the melt-quenching process. This research explores the optical and luminescence characteristics of borate glasses. Dy3+-activated glasses exhibit absorption in the visible (VIS) and near-infrared spectrums. The absorption starts from the 6H15/2 ground state to the higher state concerning optical characteristics. The emission spectra of dysprosium-doped glasses' photoluminescence show greater intensity at 483 nm (blue light) and 575 nm (yellow light), which are critical wavelengths for white light-generating materials. The luminescence intensity of Dy3+ ions increased up to a 0.50 mol% concentration, while the decay time decreased with an increasing dysprosium ion concentration. The emission spectra were used to estimate the CIE 1931 chromaticity and corresponding color temperature, revealing a shift towards the cold white light location at that temperature. The stimulated emission cross-section is calculated via the Judd-Ofelt theory. All characteristic outcomes suggest that the existing dysprosium-enabled glasses are excellent materials for generating cool white light in W-LED applications.

Optimizing white light emission in Dy(iii) complexes: impact of energy transfer from mono and bidentate ligands on luminescence.

Complexes of dysprosium(iii) ions with 1,1,1,5,5,5-hexafluoro-2,4-pentanedione featuring various mono and bi-dentate neutral ligands have been prepared and thoroughly investigated. The synthesized complexes exhibit an octa-coordinated environment, achieved by stoichiometrically combining organic ligands and Dy(iii) ions. This octa-coordination environment of Dy(iii) ion was confirmed by FT-IR spectroscopy, thermogravimetry and elemental analysis. Near-white light (NWL) is emitted when complexes were exposed to UV radiation, indicating a significant flow of energy from the sensitizing moieties towards the Dy(iii) ion. This NWL emission might have resulted due to a balance between the intensities corresponding to emission peaks at 480 nm (blue) and 575 nm (yellow) in Dy1-Dy3. Emission spectra recorded at different excitation wavelength were utilized to study the tunability of CIE color coordinates. In addition to their high thermal stability, the complexes display bipolar paramagnetic shifts in their NMR spectra. The 4F9/2 → 6H13/2 transition, contributing ∼62% of the total emission, stands out as a promising candidate for laser amplification due to its dominance in the emission spectra. Additionally, NWL emission observed in a solid Dy(iii) complex opens intriguing possibilities for its application in next-generation white-light emitting devices.

Rare earth element extraction from geothermal brine using hybrid capacitive-deionisation process

Rare Earth Elements (REE) in geothermal brine include pollutants such as dissolved Lanthanum, Cerium, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium, lithium, and other ions. These REEs in geothermal brine, also popularly known as “Vitamins of the modern industry”, are vital for industries such as new energy vehicles, wind turbines, radar systems, laser crystals, etc., and harmful for agriculture and drinking purposes. Hence, identifying, quantifying, and extracting these REEs are essential and economical for a geothermal plant. The present study systematically investigates identifying and quantifying the REE and other essential ions in geothermal brine sources from Gujarat regions. For the extraction of REE from geothermal brine, geothermal brine treatment systems and their integration with automation control are designed in the present work. The proposed system filters geothermal brine and extracts REE through a hybrid filtration setup using capacitive deionization. Solar photovoltaic Water Filtration uses a hybrid Capacitive De-Ionization (CDI) treatment-based prototype to purify water and extract REE. The CDI method is an emerging technology in the desalination systems. It has far greater leverage over other desalination methods such as electrodialysis. The proposed design allows the simultaneous removal of various dissolved organic and inorganic contaminants in geothermal brine.

Исследование механизма совместного электровосстановления ионов Dy3+ и Co2+ в эвтектическом расплаве KCl-NaCl-CsCl при 823 К

The kinetic patterns of the electroreduction of the Co2+ ion in the eutectic melt KCl-NaCl-CsCl at 823 K have been determined. It has been established that the release potentials of metallic cobalt and dysprosium on an inert tungsten electrode in the molten KCl-NaCl-CsCl system differ by approximately 1.5 V. It has been shown that with the combined content of Co2+ and Dy3+ ions in the eutectic KCl-NaCl-CsCl melt, a certain depolarization of the electroreduction of dysprosium ions takes place on the metal cobalt pre-precipitated on the tungsten electrode with the formation of intermetallic phases of different compositions based on cobalt and dysprosium. The dissolution potentials of DyxCoy intermetallic phases of different compositions were determined using switch-off chronopotentiometry.

Structural Investigation and Optical Properties of Dysprosium (Dy3+) Ions Doped Oxyfluoro Antimony Borate Glasses for Photonics Applications.

Dysprosium oxide-doped glasses with a composition of 60B2O3-10Sb2O3-10Al2O3-10NaF-(10-x) LiF-xDy2O3 (x = 0.1,0.5, 1.0,1.5,2.0,2.5 mol%) were prepared using a conventional melt-quenching technique. The glasses were characterized through various analytical investigations, including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, refractive index, density, optical absorption, excitation, photoluminescence (PL) studies, decay measurements and radiation shielding parameters. The XRD and FT-IR confirms the glassy nature and functional groups present in the titled glass. The absorption spectra were used to determine the oscillator strength of the Dy3+ absorption transitions as well as the bond created with the O-2 ion in the titled glass network. The degree of the suitability of developed glasses for lasing applications was demonstrated by radiative parameters determined using Judd-Ofelt theory. In the prepared glass samples, the optical bandgap measurements indicate the presence of non-bridging oxygen (NBOs), localization of charges and donor centers in the titled glasses. Due to the de-excitation of 4F9/2 to the corresponding 6H15/2,6H13/2 and 6H11/2 states, the PL emission spectrum shows two main strong emissions at blue(480nm), yellow (575nm) and one less emission at red (663nm). The CIE coordinates determined using PL emission spectra reveal the coordinates that are falling within the white light region. Various shielding parameters such as mass attenuation coefficient, mean free path, effective atomic number were estimated to understand the radiative shielding nature of the titled glasses. Within the addition of Dy2O3, it was found that the shielding parameters values of the titled glass samples are increasing. The Mass Attenuation Coefficient, Half Value Layer and Mean Free Path of the as prepared glasses has been compared with different types of concretes to understand the shielding effectiveness of prepared glass.

White light emitting nanocrystalline Y1−xGdxPO4:Dy3+ and improved PLQY on Gd3+ co-doping

White Light emitting phosphors are in the realm of scientific evolution owing to their several superior photophysical features and maximum commercial reach. Here in this work we have carried out doping of Dy3+ in Y1-xGdxPO4 wherein we have moved from YPO4 to GdPO4 to harness the potential of dysprosium ion in achieving white light emission and correlating the structural evolution in these phosphates with luminescence properties. Y1-xGdxPO4:Dy3+ phosphor has been synthesized using co-precipitation method and characterized using x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), time resolved photoluminescence (TRPL) and positron annihilation lifetime spectroscopy (PALS). Based on emission spectroscopy it was deciphered that Dy3+ lacks inversion symmetry in all the samples with asymmetry ratio of ∼1.2 in YPO4 and 2.75 in GdPO4. The same is correlated structurally wherein YO8 is in dodecahedron with D2d symmetry while GdO8 is highly distorted. The photoluminescence quantum yield (PLQY) increases monotonically with Gd3+ insertion and GdPO4:Dy3+ showing the highest PLQY endowed by enhanced asymmetry around Dy3+ making the f-f transitions more relaxed and allowable. The surface defects as revealed by positrons also decreased with increase in Gd content and that also aids the increase in emission intensities. Moreover PLQY value was higher with 274 nm compared to excitation with f-f transitions (∼351 nm) due to Gd3+ to Dy3+ energy transfer. The phosphors have similar color coordinate value and correlated color temperature of (∼0.33, ∼0.36), ∼5400 K, respectively, which are close to the bluish cool-white emission. Therefore, the GdPO4:Dy3+ phosphor with longer excited state lifetime, moderate PLQY, effective CIE coordinates close to white and high CCT can be explored for generation of cool white light emission excitable by UV/NUV LED for solid-state lighting and optoelectronic devices.

Two bimetallic compounds with attractive structures and properties

Two new bimetallic lanthanide-mercury isonicotinic acid compounds were successfully synthesized through classical hydrothermal reactions using DyCl3·6H2O or LuCl3·6H2O, HgCl2, isonicotinic acid, and distilled water. The resulting compounds, [Dy2(IA)6(H2O)2(H3O)2(Hg2Cl5)2]n(3nHgCl2) (1; IA refers to isonicotinic acid anions) and [Lu(HIA)(IA)2(H2O)2Hg2Cl5]2n[3n(HgCl2)]·6nH2O (2; HIA refers to isonicotinic acid), exhibit intriguing crystal structures and photophysical properties. The crystal structures of compounds 1 and 2 were determined through single crystal X-ray diffraction, revealing their two-dimensional (2D) nature. Compound 1 displays upconversion yellow photoluminescence, attributed to the 4F9/2 → 6H13/2 electronic transition of the trivalent dysprosium ion. In contrast, compound 2 exhibits blue photoluminescent emission. The Commission Internationale de I'Éclairage (CIE) chromaticity coordinates of (0.4874, 0.5115) for 1 and (0.1225, 0.0678) for 2. The correlated color temperatures (CCT) are 2960 K and 5503 K for compounds 1 and 2, respectively. Furthermore, the semiconductor band gaps for compounds 1 and 2, determined by solid-state diffuse reflectance experiments, are 2.92 eV and 4.75 eV, respectively. Additional insights into their thermal stability are provided via thermogravimetric analysis (TG) results.

Preparation, characterization and spectroscopic analyses of Dy(III) β-diketonates with bidentate N donor neutral ligands for displays

A group of octa-coordinated, anhydrous in nature luminous compounds whose general formula is [Dy(DPD)3L] where ‘DPD’ denotes 1,3-diphenylprop-1,3-dione and ‘L’ corresponds to 2,2ʹ-bipyridine and its derivatives, has been synthesised and fully characterized by CHN, FTIR, NMR and thermal analyses. Dysprosium ion is chelated with ‘O’ atoms of three bidentate β-diketones and ‘N’ atoms of one bidentate neutral ligand. The NMR spectra of synthesised complexes revealed that the protons of β-diketone and –N donor ligands are shifted in opposite direction due to paramagnetic character of Dy(III) ion. Photophysical and electrochemical characteristics of synthesized complexes were studied by absorption, photoluminescence and cyclic voltammetry techniques. The PL spectra of dysprosium ion generate its characteristic yellow emission due to the hyper intense transition i.e.,4F9/2 → 6H13/2 which is sensitive to the bonding environment of trivalent ion. The optical band gap data and branching ratio (4F9/2 → 6H13/2) confirms the effectiveness of synthesized complexes in displays and magnets.

Crystal structure and photocatalytic activity of luminescent 3D-Supramolecular metal organic framework of dysprosium

A 3D supramolecular metal organic framework of dysprosium has been fabricated through a facile hydrothermal procedure with the ligand, 2,6-naphthalene disulphonic acid and the co-ligand, 4,4′-bipyridine. The MOF has been characterized as [C60H81DyN8O30S4] by routine analytical procedures. SXRD studies of the MOF show the existence of a hydrogen-bonded 3D supramolecular structure with high porosity. It crystallizes in monoclinic space group P21/n with unit cell parameters, a = 16.5424(6) Å, b = 37.0052(14) Å, c = 24.4361(9) Å, β = 100.7410°, α = γ = 90°. The Dy-MOF has eight coordinated water molecules around the metal centre and exhibits square anti-prismatic geometry. The band gap is 3.11 eV. The degradation experiments under visible light confirmed that Dy-MOF can act as a photocatalyst. Addition of hydrogen peroxide remarkably increases the degradation efficiency of the MOF through an advanced oxidation process. The newly synthesized MOF produced sharp emission peaks characteristic of dysprosium ion.

Slow magnetic relaxation behaviors and diamagnetic dilution studies of a carboxyl bridged dinuclear dysprosium(III) complex

By using a rigid bulky carboxylic ligand α-cyanocinnamic acid (CCA), a dinuclear dysprosium (III) complex [Dy2(CCA)6 (MeOH)4] (1) was synthesized. Single crystal X-ray crystallography reveals that the two eight-coordinate dysprosium ions are bridged by four deprotonated carboxyl groups, forming a centrosymmetric paddle-wheel-like structure. Dynamic magnetic property measurements indicate that complex 1 displays field-induced slow magnetic relaxation. The temperature-dependent relaxation times can be fitted using Orbach and Raman processes with parameters of n = 2.8 (2), C = 27 (8) s−1/Kn, τ0 = 5 (2) × 10−10 s and Ueff = 40 (3) cm−1. Magnetic studies on the diamagnetic YIII-diluted analogue [Dy0.206Y1.794(CCA)6 (MeOH)4] (2) reveal its slow magnetic relaxation behavior without external dc field and the antiferromagnetic coupling between the DyIII ions in 1. Fits on the obtained relaxation times of 2 lead to the parameters of n = 4.5 (3), C = 0.7 (2) s−1/Kn, τ0 = 2.8 (2) × 10−9 s and Ueff = 38 (2) cm−1. The results suggest that slow magnetic relaxation originates from the single-ion relaxation of DyIII ions. Moreover, the diamagnetic dilution can suppress other fast relaxation pathways at low temperature, on account of the elimination of magnetic coupling and dipolar interaction. Ab initio calculations were then performed on the single DyIII ion species {YDy} and indicate that the first excited Kramers doublets (KDs) lie at ca. 76 cm−1, which is slightly higher than the experimental Ueff value. The intramolecular magnetic interactions were also calculated and indicate a weak ferromagnetic dipole-diploe magnetic interaction and an antiferromagnetic exchange coupling.

Electrochemical Behavior of Dysprosium Ion and Its Co-Electroreduction with Nickel Ions in the Molten KCl-NaCl-CsCl Eutectic

The electrochemical behavior of dysprosium ions, as well as dysprosium and nickel ion co-reduction, on inert tungsten electrodes and active nickel electrodes were studied in the eutectic KCl-NaCl-CsCl melt at a temperature of 823 K using the methods of cyclic and square-wave voltammetry and open circuit chronopotentiometry. The process of Dy3+ ions electroreduction was found to be reversible and to proceed within a single three-electron stage up to the polarization rate of 0.1 V/s. The increase in the polarization rate indicates a slower rate of the charge transfer, which causes the quasi-reversible character of the charge transfer. It is shown that when the KCl-NaCl-CsCl eutectic melt contains both nickel and dysprosium ions, the voltammetry curves at 823 K have a wave of nickel ion reduction at the potentials of −(0.22–0.28) V and a dysprosium ion reduction at the potentials of −(2.175–2.250) V relative to a chlorine-silver reference electrode. Apart from these waves, the voltammograms have two reduction waves at the potentials of −(1.9–1.95) V and −(2.05–2.1) V. These waves are associated with the reduction of dysprosium ions and their depolarization on metallic nickel, which was preliminary deposited on the tungsten electrode, as well as the formation of the intermetallic phases of dysprosium and nickel of various DyxNiy compositions. The (E-t) dependencies of the open circuit chronopotentiometry elucidate plateaus of the potential delay, which correspond to the dissolution of separate dysprosium and nickel intermetallic phases. Based on the results of the voltammetry changes and the chronopotentiometry of the open circuit, a series of electrochemical syntheses were performed in the potentiostatic regime at the potentials of −(1.7–2.1) V. The intermetallic phases of DyNi5, DyNi3 and DyNi2 were obtained at a definite ratio of the dysprosium and nickel chloride concentrations in the KCl-NaCl-CsCl eutectic melt and at a temperature of 823 K. The synthesized intermetallic samples were characterized by X-ray diffraction and scanning electron microscopy.

An insight into the transition metal dependent structural, optical, and electrical properties of dysprosium doped lithium zinc borate glasses

A glass series of Dy3+ ions doped zinc vanadium lithium borate with chemical composition xV2O5·(10-x)ZnO·30Li2O·60B2O3 (x = 0, 1, 5, 7, 9, 10) with 1.0 mol% of Dy2O3 has been synthesized by melt quench method. Efforts have been made to identify suitable optoelectronic material by studying the structural, electrical, photo-luminescence (PL), and optical characteristics of the dysprosium ions in the presence of VO2+ ions. PL emission spectra have been explored, depicting that when excited at 386 and 424 nm, the glass matrix is suitable for laser action and at 452 nm, it is apt for cool white light applications.

Synchrotron studies of Ag+ and Dy3+ ions in zinc lanthanum aluminum borate glasses synthesized using Novel Microwave melt-quenching technique

A novel microwave heating technique is used in the present work to synthesis the glasses. In this work, the stoichiometry ratio of (43-x) B2O3+ 45ZnO+ 5La2O3+ 5Al2O3+ 0.5SnO2+ 1.5AgNO3+ xDy2O3 were exposed to microwave energy, with 800-W power, holding time was 26 min to synthesize by novel melting in microwave and quenched suddenly. The study focused on borosilicate glasses such as physical, optical, and luminescent characteristics. The prepared glasses were subjected to evaluate density, molar volume, and refractive index. The optical absorption spectra of glasses were measured in the range of 200–2000 nm. The surface plasmon resonance of AgNPs peaks resonates with the radiative transitions of Dy2O3 ions at 429 nm. The emission spectra in the visible region showed three peaks in the range 450–700 nm, and the excitation spectra of developed glass samples in the range of 200–500 nm, most intense peak was observed at 351 nm. Asymmetry ratio enhancement was achieved by changing the excitation wavelength and silver nanoparticle concentration. The highest Y/B value of 1.532 was observed at 1.0 mol%. The non-exponential lifetime decay curves of 0.3, 0.5, and 1.0 mol%, show 0.337, 0.376, and 0.269 ms respectively. J-O parameter shows trend Ω2 > Ω6 > Ω4. Synchrotron studies were subjected to comprehend the coordination chemistry of silver nanoparticles, dysprosium ions, and correlated with the results obtained.

Optical analysis of RE3+ (Sm or Dy): B2O3-P2O5-CaF2-ZnO – (Li2O/Na2O/K2O) glasses

This article presents synthesis of mixed boro flouro phosphate glasses doped with trivalent samarium and dysprosium ions by melt quenching technic and the luminescent spectra of the glasses and their modifications by altering alkali oxides. Fourier transform infrared spectroscopy (FTIR) tool is used to detect various functional groups their bonding nature in host glasses .The luminescent spectrum of Sm3+ exhibits Orange-Red emission at wavelength of 599 nm due to transition from 4G5/2 →6H7/2 and Dy3+ spectrum has shown yellow emission at wavelength of 575 nm from 4F9/2 →6H13/2 by strong excitation at 403 nm and 388 nm 6H5/2 →4F7/2 transition of Samarium (Sm3+) ion and 6H15/2→4I13/2 transition of Dysprosium (Dy3+) ion respectively. In this article, by altering the three different alkali oxides (Li2O/Na2O/K2O) with the same concentration (0.5%) of Dy3+ ions and Sm3+. The change in the luminescent intensities were studied.