Doped Borate Glasses Research Articles

The study on Er3+ doped lithium bismuth aluminium borate glass for infrared medium applications

In this work, lithium bismuth aluminium borate glasses doped with different concentration of Er2O3 were prepared to investigate the physical, chemical group, optical and luminescence properties. All glasses were prepared by melt-quenching method. Glass density is in a range of 3.20 – 3.27 g/cm3 with no obvious relation to Er2O3 concentration. The FTIR spectra confirm the trigonal BO3 and tetrahedra BO4 borate unit appearing in glass network. This BO4 unit and non-bridging oxygen tend to increase with increment of Er2O3 content. Er3+ in glass absorb photon in visible light and near-infrared region, confirmed by the absorption spectra. The emission and excitation spectra perform the infrared emission of Er3+ under 523 and 977 nm excitation. The strongest emission with 1536 nm belongs to 1.00 mol% Er2O3 doped glass that was excited by photon with 523 nm. This developed glass possesses the good potential for using as the source and medium material for infrared emitting and communication device.

Structural and optical properties of Sm3+-doped borate glasses for luminescent applications

In this work, most interesting optical investigations are carried out with the glass composition (20 − x) CdCO3 + 15 Li2CO3 + 15 Na2CO3 + 50 H3BO3 + xSm2O3 (where x = 0.1, 0.5, 1.0, 3.0, 4.0 and 5.0 mol%) prepared with conservative melt-quenching technique. DSC verifies the annealing temperature and thermal stability of the prepared glass. X-ray diffraction technique is employed to inspect the amorphous structure of the glasses. FTIR technique helps to view the vibrational band positions of the host material. For optical studies, optical absorption and emission measurements are used. From the absorption spectra, Judd–Ofelt (JO) parameters (Ω2, Ω4, Ω6), rms value of oscillator strength ($$\delta_{rms}$$), nephelauxetic parameter ($$\bar{\beta }$$), bonding parameter ($$\delta$$) and optical band gaps are evaluated. Radiative properties such as radiative transition probabilities (AT), branching ratios (βcal, βexp) and stimulated emission cross section (σemi) are calculated using JO theory. The higher stimulated emission cross section (14.39 × 10−22 cm2), optical gain (36.69 × 10−25 cm2 s) indicate that 1.0 mol% of Sm3+-doped borate glass would be a potential gain medium for solid state laser application at 603 nm. Color coordinates of the glasses located in the reddish-orange region could be useful for white light-emitting application.

Optical spectroscopic study of cobalt oxide doped boron glass and its ion effect on optical properties

In this paper, the optical spectroscopic properties of Co3O4 doped borate glass with chemical composition: 60 B2O3, 30 ZnO, (10-x) Na2O, x Co3O4, (where x= 0 (S0), 0.1 (S1), 0.2 (S2), 0.3 (S3), 0.4 (S4), 0.5 (S5) mol %) were investigated. The glass samples (S0-S5) were prepared by conventional melt quenching technique. The formability of all prepared glass samples was examined by XRD and UV–visible spectroscopy techniques. The amorphous nature of glass structure was confirmed by XRD- technique. Archimedes method was used to measure density and calculate the molar volume of the prepared glass composition. It was observed that the density and molar volume of processed glass samples increased by increasing concentration of Co3O4. The optical spectroscopic characteristics of the obtained borate glass have been carried out over the whole range (190-2500nm) for studying the bandpass glass filter and UV cut-off. Through experimental data it was observed that the optical energy gap decreased from 3.25 to 3.03 eV by increasing doped cobalt oxide contents on borate glass. Furthermore, UV cut-off regions increased by increasing concentration of cobalt oxide. The effect of doping concentration on the optical properties of the prepared glass samples (refractive index, extinction coefficient, permittivity, dielectric constants, electric susceptibility and polarizability) was determined and studied.

Physical, optical properties and radiation shielding studies of xLa2O3-(100-x)B2O3 glass system

Herein we prepared five glass samples from the composition xLa2O3-(100-x)B2O3 (where x = 15, 20, 25, 30 and 35 mol%) and reported the physical, optical and gamma radiation shielding characteristics. The density of glass samples was increased from 3.1531 to 3.9443 g/cm3 with the addition of La2O3, while the molar volume is in the range of 34.2679–40.3849 cm3/mol. The refractive index of the glass samples is in the range of 1.6524–1.6541 with addition of La2O3 concentration. The optical band gap energy is found to be in the range of 3.08–3.14 eV. The transmission spectra for the La2O3 doped borate glasses in the wavelength range 200–2200 nm were reported and the results showed good transparency in visible region. This indicates that the prepared glasses are specifically showing superior transparency to visible light. The mass attenuation coefficient (μ/ρ) was simulated using MCNP code and the simulated data were compared with WinXcom data. The radiation shielding results showed that the different concentrations of La2O3 for the La2O3–B2O3 glass system have affected the μ/ρ of the glasses. Moreover, the sample with 35 mol% of La2O3 has higher μ/ρ compared with the rest of specimens especially at 0.347 MeV. The effective atomic number (Zeff) was also calculated and the highest Zeff values at all selected energies were for the sample with 35 mol% of La2O3, whereas the lowest Zeff were for the sample corresponding to 15 mol% of La2O3, which was 18.86 and 12.31 at 0.347 MeV respectively. The mean free path at 0.347 MeV and 0.511 MeV is very low for 35 mol% of La2O3 (1.88 and 2.70 cm respectively), which indicates that the sample with composition 35La2O3–65B2O3 can be used as effective and transparent photon shieling materials at low energy.

Sm3+ Doped Lithium Strontium Borate Glasses for Solid State Lighting Applications

The glasses of samarium (0.1, 0.2, 0.5, 1.0, 1.5 and 2.0 mol %) doped lithium strontium borate samples were synthesized. The physical and optical properties are studied at ambient conditions and discussed in this study. XRD spectra reveals the no atomic order in structure (amorphous) present in these glasses. Infrared spectroscopic study reveals the structural units of borate viz., BO3 and BO4 group present in the matrix. Interestingly, it is found that as the rare earth concentration increases and beyond 1.5 mol % the luminescence intensity decreases due to non-bridging Sm3+ ions in the glass network. The peaks in absorption spectra are due to dipole transition from 6H5/2 to levels corresponds to (2S + 1)LJ excited states under the excitation wavelength of 402 nm. Judd–Ofelt theory applied to estimate dipole strength in terms of J–O parameters (Ω2, Ω4 and Ω6), oscillator strength (fexp and fcal), radiative transition possibility (AR), branching ratio (βR) and stimulated emission cross section (σ) of the glass samples. From Judd–Ofelt analysis the parameters obtained are shown for 1.50 mol % of Sm3+ doped lithium strontium borate (LSB) glasses studied, which were compared with other glasses. The obtained results suggest their potential candidature for using as solid state material lighting applications due their efficient orange emissions.

An extensive investigation of physical, optical and radiation shielding properties for borate glasses modified with gadolinium oxide

We prepared four Gd2O3 doped borate glasses and investigated their physical, optical and radiation shielding features. The density of glass samples was increased linearly with the Gd2O3 content. The transmission spectra of the samples show more than 85% transmittance suggesting their superior transparency in the visible region. The band gap decreases with increase in Gd2O3 content. The Geant4 code was used to find the attenuation factor for the samples between 0.284 and 2.506 MeV. The results demonstrated that the transmission factor changes from 51% (corresponding to 20 mol% of Gd2O3) to 39% (for 35 mol%) at 0.284 MeV. The addition of Gd2O3 affects highly the mass attenuation parameter at 0.284 and 0.347 MeV. The effective atomic numbers of the glass sample corresponding to 20 mol% of Gd2O3 are in the range 12.06–18.79. The maximum tenth value layer was observed for 20 mol% of Gd2O3 sample (15.768 cm).

Determination of Judd-Ofelt parameters for Eu3+-doped alkali borate glasses

The radiative transition properties of Eu3+ doped materials can hardly be quantitatively evaluated via traditional Judd-Ofelt (J–O) calculation procedure owing to the lack of available transitions in the absorption spectra. In this work, a new J–O calculation route was proposed and employed to Eu3+ doped alkali borate glasses. Three sets of J–O parameters were obtained by using, respectively, the absorption, emission and excitation spectra, and the average J–O parameters involving more electric dipole transitions than in any individual spectrum were suggested to be used for quantificationally presenting radiative transition properties of Eu3+ in the studied glasses. The radiative transition lifetime of 5D0 level derived by using the J–O parameters was compared with the measured one, and good agreement was achieved. This fact indicated that the proposed J–O calculation route is practicable. Furthermore, the radiative transition rates and fluorescence branching ratios for Eu3+ in the studied borate glasses were calculated.

Molecular dynamics simulation and luminescence properties of Eu3+ doped molybdenum gadolinium borate glasses for red emission

The contribution reports on molecular dynamics simulation were used to understand, at the molecular level, the interaction of molybdenum, gadolinium and europium ions with neighboring oxygen. Molecular dynamics simulations were carried out to evaluate the bond distance between Gd–Eu and Mo–Eu and found that the Gd–Eu bond distance is larger than for Mo–Eu. Various spectroscopic characterizations were employed to comprehend their optical and structural properties for their interconnectivity. Computational analysis was employed which emphasizes the radial distribution functions and their co-ordination numbers around Gd, Mo and Eu atoms. Phonon Side Band (PSB) spectrum associated with 7F0→5D2 transition of Eu3+ ions confirms the phonon energy of the prepared glass which was reconfirmed with FTIR and Raman spectra. The oscillator strength with and without thermal corrections was calculated from absorption spectrum to evaluate Judd-Ofelt (JO) analysis and JO parameters were estimated for 0.5 mol% Eu2O3 doped 25MoO3–20Gd2O3–(55-x)B2O3 glasses. Radiative properties such as transition probabilities, stimulated emission cross-sections and branching ratios were estimated by using JO parameters and luminescence spectra. The decay time and CIE coordinates have been calculated for prepared glass samples.

Structural and spectroscopic properties of Er3+ doped sodium lithium borate glasses.

The trivalent erbium (Er3+) doped sodium lithium borate glass with composition (65-x)B2O3-15Na2O-10PbO-5ZnO-5Li2O-xEr2O3 have been successfully fabricated by melt-quench technique. The structural properties were investigated by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR). The absorption and luminescence spectra of glass samples were measured to determine the spectroscopic properties. The Judd-Ofelt parameters were calculated based on absorption spectra with values of Ω2, = 4.39, Ω4 = 3.22, and Ω6 = 0.91 (×10-22 cm2) for 2.0 mol% Er3+ ion doped sodium lithium borate glass. Furthermore, radiative properties including effective bandwidth (Δλeff), radiative transition probability (AR), radiative lifetime (τR), and branching ratio (βR) were also calculated and analyzed. A strong emission band at 1532 nm was observed corresponding to 4I15/2 → 4I13/2 transition under the excitation wavelength of 528 and 976 nm. The stimulated emission cross-section (σe) and figure of merit (FWHM xσe) were calculated and compared with other glasses in order to evaluate the properties of the present samples for optical amplifier. Based on the characterization results, we found that the glass with 2.0 mol% Er3+ ion doped sodium lithium borate glass had the highest stimulated emission cross section compared to other samples and were comparable with the previous reports.

Luminescence characteristics of Nd3+ doped bismuth borate glasses for photonic applications

Nd3+ doped BBZPA glasses were prepared by conventional melt quenching method and used to study their structural, absorption, emission and decay properties. From XRD, amorphous nature of the undoped glass has been confirmed. The J-O intensity parameters Ωλ (λ = 2, 4, 6) and the various radiative parameters were calculated from J-O analysis. From the emission spectra, it is observed that, the laser transition 4F3/2 → 4I11/2 at 1059 nm is more intense transition. The decay curves for prepared glasses exhibited single exponential decay. The above results suggest that Nd3+ doped BBZPA glasses could be suitable for photonic applications.

Dazzling red luminescence dynamics of Eu3+ doped lithium borate glasses for photonic applications

A series of distinct concentrations of Eu3+ doped lithium borate glassy matrices were prepared by melt quenching technique and their structural and luminescence characteristics have been studied. A wide hump exhibited in X-ray diffraction spectrum and smooth surface from SEM analysis affirms the nebulous behavior of the obtained glassy matrices. A strong excitation band noticed at 393 nm (7F0→5L6) correlated with the excitation wavelength of near-UV LED chip. By exciting with 393 nm, photoluminescence spectra reveals a strong red emission at 612 nm (5D0→7F2). Luminescence intensity has been embellished remarkably with rising Eu3+ concentration up to 1.0 mol % which can be identified as optimized concentration. At higher concentrations of Eu3+, emission intensity has been decreased due to concentration quenching. The excited level 5D0 lifetime is computed and it is evaluated to be 2.57 ms from the decay profile of 1.0 mol % Eu3+: LBZ glassy matrix. CIE color coordinates have been calculated from the luminescence spectra, which indicates strong red emission. Based on the luminescence spectral features, 1.0 mol % Eu3+: LBZ glassy matrices could be suggested as favorable candidates for the application of reddish orange emission photonic devices.

The effect of CeO2 on the thermal stability, structure and thermoluminescence and optically stimulated luminescence properties of barium borate glass

Cerium doped barium borate glasses were prepared in the BaO-B2O3 system. The effect of CeO2 admixture on thermal stability and structure of the glass was developed. Thermoluminescence (TL) and optically stimulated luminescence (OSL) properties, such as glow curves, linearity of dose-response and decay curves were presented. The results showed that the increase of cerium dopant concentration from 1 to 5 mol% promotes the [BO4] formation and causes the efficiency enhancement of TL by more than ten times and OSL by more than one hundred times. Based on the XRD patterns we can state that a new phase of BaCeB9O16 was obtained, which is not present in the structural databases. The Rietveld analysis showed that the phase is isostructural to BaLaB9O16. Controlled crystallization of cerium doped borate glasses revealed that formation of the glass-ceramics can enhance the intensity both of TL and OSL processes.

Physical, structural and optical properties of Sm3+ doped lithium zinc alumino borate glasses

Sm3+ doped lithium zinc alumino borate glasses with composition 15ZnF2–12Li2CO3–10BaO–8Al2O3–(55-x)B2O3–xSm2O3 where x = 0.1, 0.3, 0.5, 0.7 and 1.1 mol% were prepared by conventional melt quenching technique Their optical, physical, structural, mechanical and luminescence properties are investigated. UV–Vis-NIR absorption spectra showed all possible transitions of samarium ion in this glass matrix. Band gap values for all the glass samples were above 3 eV confirming the insulating nature for the glass. Densities, assessed using the Archimedes rule, were observed to be increasing with increasing samarium concentration. Increase in molar volume with addition of samarium content indicated that the extension of glass network is on account of the increase of number of Non-Bridging Oxygens created by network modifier samarium ions. Scanning Electron Microscopy (SEM) image showed a smooth surface for the synthezied glass. X-Ray Diffraction (XRD) technique was employed to verify the amorphous nature of the glasses. A Makishima and Mackenzie theoretical model gave acceptable approximation of elasticity constants viz. Young's modulus, shear modulus, bulk modulus and Poisson's ratio. The high Vickers hardness values evaluated with mechanical loads of 50, 100, 300, 500, 1000 g force, proved the stability of the glasses. Emission spectra showed a prominent transition 4G5/2 → 6H7/2 at 598 nm excited with 6H5/2 → 4P3/2 transition at 401 nm. Luminescence quenching effect was observed beyond 0.3 mol% Sm2O3 addition. The chromaticity coordinates (x, y) clustered in the orange-red region, making these Sm3+ doped lithium zinc alumino borate glasses suitable candidate for applications in LEDs and solid-state lasers.

Investigations on structural and radiation shielding properties of Er3+ doped zinc bismuth borate glasses

Novel optical glasses 10ZnO-5Na2CO3-10Bi2O3-(75-x)B2O3-xEr2O3 with x = (0, 0.1, 0.3, 0.5, 0.7, 1.0) mol%, were synthesized by melt quench technique and characterized through XRD, EDAX, optical and luminescent properties, before and after irradiating them with high energy (1.3 MeV) gamma rays. Moreover, the gamma photons attenuation characterizations for the samples under study were studied. The mass attenuation coefficients for the selected glasses were affected with the addition of Er2O3. Based on the findings from the mass attenuation coefficients, ZNBBEr-5 has better photon attenuation features in comparison with the other samples. Also, arising the Er2O3 content in the glasses, led to increase the effective atomic number. The mean free path for the prepared samples were compared with some shieling glasses. Shielding performance of the present glass samples against gamma radiation reveals pair production is prominent at 1.3 MeV. UV-VIS–NIR absorption edge was red shifted after gamma irradiation indicating the formation of electron/absorption centers in the glass matrix. Thermally stimulated Luminescence (TL) spectroscopy technique showed five electron trap centers at 445K, 491K, 545K, 590K, 620K with acceptable FOM [< 5%] values. The number of overlapping peaks and their trapping parameters like kinetic order, activation energy, peak temperature, frequency factor and half life were determined using the Computerized Glow Curve Deconvolution (CGCD). Linear behaviour obtained through the dose response of the glass (5 kGy–50 kGy) proved their suitability for dosimetric application in the food irradiation zones and in red LEDs (<50 kGy).

Mixed alkali effects in Er3+‐doped borate glasses: Influence on physical, mechanical, and photoluminescence properties

AbstractEngineering borate glass structure by simple compositional modification is essential to meet the particular demands from both industrial and photonic research communities. In this article, we demonstrate how the mixing of Li2O with Na2O, K2O, or Cs2O influences the relative abundance of 3‐ and 4‐coordinated borons in the glass network, as exhibited by nuclear magnetic resonance (NMR) and Raman spectra. A systematic study is given of the alkali mixing effect on the glass properties including: glass transition temperature, microhardness, density, refractive index, and particularly the near‐infrared photoluminescence properties (eg, bandwidth and lifetime) of Er3+ which has been barely studied in mixed alkali borate glasses. It is interesting to note that the glass transition temperature, refractive index and emission lifetime of Er3+ manifest mixed alkali effect, in sharp contrast with microhardness, density, and emission bandwidth which vary monotonically upon the alkali mixing. The possible causes for the differences are discussed in the light of the compositional dependence of boron species and nonbridging oxygen upon alkali mixing.

Influence of 1.25 MeV gamma rays on optical and luminescent features of Er3+ doped zinc bismuth borate glasses

Abstract Glasses based on 10ZnO-5Na2CO3-10Bi2O3-(75-x)B2O3-xEr2O3 with x = (0, 0.1, 0.3, 0.5, 0.7, 1.0) mol%, were synthesized by melt quenching technique and characterized through optical and luminescent features, before and after irradiating them with high energy (1.25 MeV) gamma rays. The amorphous nature of the glasses and the presence of various structural groups like BiO6, BO3 and BO4 were confirmed through XRD and FTIR measurements. Optical properties were studied through UV–VIS–NIR absorption spectra. Decrease in band gap values after gamma irradiation confirmed the creation of color centers in the glass matrix. Thermally stimulated Luminescence (TL) and Optically Stimulated Luminescence (OSL) spectroscopy techniques were used to study the trap centers induced after irradiation. The number of peaks and their trapping parameters were assessed using the Computerized Glow Curve Deconvolution (CGCD). The linearity in dose response proves their suitability in usage for dosimeter and shields in radiation zones within the dose.

Tm3+/Tb3+/Eu3+掺杂硼酸盐玻璃陶瓷的能量转换和发光性能

Tm³⁺/Tb³⁺/Eu³⁺掺杂硼酸盐玻璃陶瓷的能量转换和发光性能

Influence of alkaline earth oxides on Eu3+ doped lithium borate glasses for photonic, laser and radiation detection material applications

50Li2O - 20MO - (30-x)B2O3 - xEu3O3 where (M = Mg, Ca, Sr, Ba) and (x = 0, 0.1, 0.3, 0.5, 1.0, 3.0, 5.0, 7.0 glasses were prepared and characterized to study their physical & optical properties using spectroscopic measurements such as UV-Visible spectra, Luminescence spectra, Radio-Luminescence, X-Ray Luminescence etc. The electronic transitions in the UV-VIS and NIR regions are assigned to the 7F0 → 5L6, 7F0 → 5D2, 7F0 → 5D1, 7F0 → 7F6 and 7F1 → 7F6 levels centered at 394, 465, 532, 2092 and 2202 nm due to their transitions from 7F0 ground state to various excited states of Eu3+ ions, respectively. Structural studies were analyzed using Raman Spectra. Five transition bands of luminescence spectra have been observed by using an excited wavelength of 394 nm. With five emission transitions of 5D0 → 7F0, 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3 and 5D0 → 7F4 as was reported previously in literature at 578, 591, 591, 614, 653 and 702 nm, respectively. The lower phonon energy (∼971 cm−1) and higher phonon side band intensity is observed at 5.0 mol% Eu2O3 content doped LBaB glasses while higher phonon energy (∼1176 cm−1) and lower phonon intensity observed for 5.0 mol% Eu2O3 content doped LMgB glasses. The chromaticity coordinates of Eu3+ ions in all LiMOB glasses falls in the reddish orange region. The radioluminescence (RL), emission spectra were corresponding to those from PL measurements. From RL measurement, the integral scintillation efficiency of developed glass was determined at 11.2% when compared with BGO crystal.

Effects of high dose gamma irradiation on the optical properties of Eu3+ doped zinc sodium bismuth borate glasses for red LEDs

Interaction of 10ZnO-5Na2O-10Bi2O3–74.3B2O3-0.7Eu2O3 glasses exposed to high dose gamma rays were investigated using XRD, FTIR, absorption, photoluminescence followed by thermally and optically stimulated luminescence studies. XRD analysis confirmed the amorphous nature of glasses post-irradiation. Variation in FTIR spectra revealed, structural deformation of borate groups as a result of high dose gamma irradiation. Enhanced glass absorbance and red shift in absorption edge were observed with the increase in gamma dose. Further, radiation-induced absorption coefficient confirmed the trapped charges in the forbidden energy gap supported by Tauc's plot and Urbach energy. Photoluminescence (PL) study demonstrated quenching of luminescence intensity at higher gamma doses. Lifetime of metastable 5D0 state of Eu3+ ions were estimated by the decay curves and color purity was calculated using 1931 CIE chromaticity coordinates (x,y). Thermally and optically stimulated luminescence studies reassured the existence of charges in trap centers due to irradiation. TL glow curve exhibited two broad emission peaks with the corresponding temperature being at 490 K and 625 K. Distinct TL peaks of the material and their kinetic parameters (E, S, τ and b) were determined via Computerized Glow Curve Deconvolution (CGCD) method. Linear behaviour obtained through the dose response of the glass (0.25–3 kGy) proved their suitability for dosimetric application in the food irradiation zones in addition to red LEDs (< 1 kGy).

Mixed transition and rare earth ion doped borate glass: structural, optical and thermoluminescence study

The present work report on physical, structural, optical and thermoluminescence properties of Dy3+ doped manganese potassium borate glasses. The conventional melt quenching technique is used to prepare the glass samples. The amorphous nature of the prepared glass sample is confirmed by X-ray diffraction study. The different B–O vibrational bands and change in the coordination number of boron (BO3 → BO4) with the inclusion of Dy3+ ions in the prepared glasses were analyzed through FTIR. The physical parameters such as density, molar volume, average molecular weight, ion concentration, polaron radius, internuclear distance and optical parameters have been determined. The optical analysis reveals that the optical band gap energy decreases with the increase of dysprosium oxide concentration. The TL glow curve of gamma irradiated samples showed single prominent peak in the temperature range 425–460 K with varying concentration of Dy2O3. Analysis of kinetic parameters reveals that the glasses demonstrate second order kinetics.