Borate Glass System Research Articles

Judd−Ofelt calculations for spectroscopic characteristics of Dy3+-activated strontium magnesium borate glass

Some new type of strontium magnesium borate glass system doped with Dy3+ (various contents 0.1, 0.3, 0.5, 0.7 and 1.0 mol%) were produced using the conventional melt-quenching. Obtained glasses were thermally stable, highly transparent, and moisture resistant. As-prepared samples were characterized to determine their spectroscopic traits. The Judd-Ofelt (J-O) intensity Ωλ (λ = 2, 4, 6) and radiative parameters were calculated to validate the experimental results on the optical characteristics. The XRD pattern of the as-quenched samples verified their glassy nature, FESEM images showed uniform textures and EDX analyses detected the presence of appropriate constituents in the host matrix. Glass containing 0.7 mol% of Dy3+ revealed the optimum optical traits where the luminescence emission intensity was attenuated beyond this content. The optical gain for two intense emission transitions (4F9/2→6H15/2 and 4F9/2→6H13/2) was evaluated. The values of Ωλ (λ = 2, 4, 6) determined the ionic nature of the bonding and symmetry environment of the Dy―ligand matrix based on the viscosity and rigidity of the host glass. The 6H15/2→6F11/2 transition was hypersensitive. The ratio of the yellow to blue (Y/B) emission intensity less than unity indicated the lower degree of covalence between Dy3+ and O2− ions thereby makes these glasses effective for the near UV―LEDs. The higher values of the branching ratio (≥ 50 %) and stimulated emission cross-section enabled the proposed glass composition potential for the optical amplifiers and fibres fabrication. The resonant energy transfer and cross-relaxation processes in the Dy3+ were attributed to be responsible for the improved optical features.

Direct influence of mercury oxide on structural, optical and radiation shielding properties of a new borate glass system

A series of barium sodium borate glasses of chemical composition (60-x) B2O3+20Na2O2+20BaCO3+x HgO, (where x = 0, 2.5, 5, 7.5, 10, 12.5, and 15 wt%) doped with mercury oxide was synthesized. The melt-quenching method was used to synthesize the glass series at 1100 °C for melting and 60 min for annealing at 300 °C. X-ray diffraction was used to study the structure of the synthesized samples at room temperature between 10° and 70°. We used a Tensor Model 27 FTIR spectrometer to show the absorption bands of the OH-, Ba+2, Hg+2, and other borate groups between 400-5000 cm-1 with a resolution of 4 cm-1. A UV–Vis–NIR spectrophotometer was applied to estimate the optical properties of the synthesized glasses. The ability of the synthesized glasses to attenuate ionizing radiation was examined using a Monte Carlo simulation (MCNP code) and the Phys-X program. Shielding factors such as the mass attenuation coefficient (MAC), half value layer, mean free path, effective atomic number, and energy absorption buildup factor (EABF) were evaluated. The effect of HgO and the energy of the photons on these parameters were discussed. The results showed that increasing the amount of HgO improved the gamma ray shielding capacity. The glass with a high amount of HgO (15 wt%) had the best shielding properties among the synthesized glasses.

Radiation shielding properties of bismuth borate glasses doped with different concentrations of cadmium oxides

The current study is aimed to investigate the gamma ray and neutron shielding properties of the bismuth borate glass system with various concentration of cadmium oxide (0, 5, 10 and 15 mol%). The XRD spectra confirms the amorphous state of the prepared samples. A number of physical and mechanical properties (molar volume, oxygen molar volume, oxygen packing density, Poisson’s ratio, optical absorption and dissolution rates) have been determined. The mass attenuation coefficients were estimated at different energy levels by using XCOM and EXABcal programs. The gamma and neutron beam shielding properties are evaluated through the calculation of several parameters such as equivalent number, specific gamma ray constant, gamma dose rate, specific absorbed fraction of energy and total neutron removal cross-section. Comparing with the standard gamma ray shielding materials, the new composition exhibits promising properties in terms of mass attenuation, halve value layer and mean free path. The glass with the highest concentration of CdO was found to be good shielding material for neutrons compared with some standard shielding materials (water, graphite, ordinary concrete and hematite-serpentine concrete).

Density and Molar Volume of Bismuth Oxide Doped Lithium Lead Borate Glass System

This work mainly focuses on the study of the density and molar volume of bismuth oxide doped lithium lead borate coded as LPBB glass system. These glasses were prepared by conventional melt quench method, in order to study their structure. Variation in the value of both density and molar volume as the mole concentration of bismuth content in lead-borate glasses was studied. Variation of density of present glasses is exactly opposite to that of molar volume with increasing mole concentration of bismuth oxide. The F.T.I.R Analysis of LPBB glasses discovered that the network structure mainly depends on the BO3 and BO4 units. Because of the role played by PbO as a glass modifier the transformation of [BO3] units to [BO4] units takes place.

Investigation of structural and ultrasonic properties of ternary borate glass specimen

New ternary calcium borate glass systems of composition 60B2O3-(40-x) CaO-xCuO, (where x = 5, 10, 15 & 20) were successfully prepared by melt quenching technique and characterized by XRD, SEM and ultrasonic measurements. The non-existence of Bragg peaks in the XRD patterns identifies the amorphous nature of the samples. SEM is carried out to study the morphological modification created by the modifier oxide. The ultrasonic velocities and Density are measured at room temperature using pulse echo overlap method and Archimedes’ principle using deionized water as immersion liquid respectively. The elastic moduli such as longitudinal, shear, bulk and Young’s moduli, Poisson’s ratio, acoustic impedance, micro hardness and Debye temperature are calculated using the measured data. These parameters are discussed due to variations in composition as well as modifying action of CuO. In this glasses, CuO plays a network former role.

A solid-state colorimetric fluorescence Pb2+-sensing scheme: mechanically-driven CsPbBr3 nanocrystallization in glass.

Highly toxic Pb2+ poses a great threat to the health of human beings and ecosystems, urgently calling for an efficient Pb2+ detection method. Herein, we demonstrated a brand-new solid-state fluorescence Pb2+-sensing scheme based on a type of Pb2+-responsive borate glass powder that is able to precipitate CsPbBr3 nanocrystals on the glass surface upon grinding with Pb2+ sources, following a mechanically driven glass crystallization mechanism. Pb2+ sensing is achieved via the Pb2+ concentration-dependent green emission of CsPbBr3 as an indicator signal and independent red emission of Eu3+ as a reference signal. Under UV light irradiation, the obvious emissive color variation from red to green as Pb2+ concentration varies enables the intuitive Pb2+-sensing by naked eyes. With the aid of a spectrometer and smartphone, Pb2+ concentration can be quantitatively determined with the detection limit as low as ∼70 ppm and ∼400 ppm, respectively. The semi-quantitative Pb2+ detection is also possible by comparing the emissive color with the calibrated color card. Hopefully, the proposed solid-state fluorescence Pb2+-sensing strategy with high selectivity can be used for portable and quick Pb2+ analysis in daily life.

Influence of ZrO2 on gamma shielding properties of lead borate glasses

In this paper, new lead borate glass system in the chemical form of 40B2O3–40PbO–20Li2O3–xZrO2; where x = 0, 0.25, 0.50, 1, and 1.5 mol% has been synthesized. Gamma-ray shielding properties of these glasses have been tested in terms of mass attenuation coefficient (μ/ρ), half value layer (HVL), effective atomic number (Zeff), mean free path (MFP), and exposure build-up factor (EBF). The μ/ρ values of the prepared glasses were generated by FLUKA Monte Carlo simulations over an extended energy range of 0.015–15 MeV, and then, the generated data were verified using the calculated values of XCOM software. The results showed that gamma-ray shielding ability of BPLZ0.00 is superior among the other prepared glasses. Moreover, the gamma-ray shielding properties of the current glass system have been compared with that of some commercial glasses and newly developed HMO glasses. It can be concluded that the prepared glass system could be useful to design and/or develop novel shields for radiation protection applications.

Synthesis of [formula omitted] glass system for the analysis of structural, optical and thermoluminescence properties

Neodymium doped sodium strontium borate (Nd3+:NaSrB) glass system has been synthesized using conventional melt quenching technique. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, Diffused reflectance spectro-scopy (DRS) and Thermoluminescence (TL) characterization have been done to observe the effect of neodymium oxide concentration on physical, optical and dosimetric properties of the prepared glass system. XRD pattern exhibit two broad humps and the close analysis revealed the presence of rare-earth induced nano-cristoballite. FT-IR spectra have been deconvoluted to study the presence of different structural groups. Band-gap (Eg) has been calculated using the Kubelka-Munk method and is found to be sensitive to Nd2O3 concentration. Maximum TL intensity is obtained for the 0.2 mol% concentration of rare-earth oxide and the shift in the peak towards lower temperature with the inclusion of Nd2O3 indicates the formation of low-level traps. Our results suggest that, due to high TL efficiency, the glass sample with 0.2 mol% concentration of Nd2O3 is suitable for the dosimetric applications.

Radiation shielding and physical properties of lead borate glass-doped ZrO2 nanoparticles

Zirconium oxide (ZrO2) nanoparticles have been prepared and examined by XRD. The transparent lead alkali borate glass systems of formula xZrO2–20PbO2–(80 − x)·Na2B4O7 (0 ≤ x ≤ 24 mol%) are prepared by melting quench method and doped by zirconia nanoparticles. Deconvolution of its FTIR reveals to increase the N4 fraction boron atoms. This result reveals the Zr4+ which forms BO4 network units. The density and refractive index of chosen glass are increased due to add of ZrO2 nanoparticles. Both ultrasonic velocities (longitudinal vL and shear vT) increase with the ZrO2 content increase. The packing density, bulk modulus and Young’s modulus increase with increasing of ZrO2 nanoparticle content. The attenuation coefficients of the studied glasses have been measured at different energies (356, 662, 1173 and 1332 keV) using narrow beam transmission geometry. The obtained results indicated that, the values of the mass attenuation coefficient (µm), the effective atomic number (Zeff) and effective electron density (Nel) of the glass samples decreased with the increase in the ZrO2 concentration at the energies (662,1173and 1332 keV), while these parameters (µm, Zeff and Nel) increased with the increase in the ZrO2 concentration at 356 keV. The samples are irradiated 30 min by argon glow discharge plasma (GDP). The values of optical band gap decreased slowly with ZrO2 nanoparticles increased and after plasma irradiation.

Comparative impact of Nd3+ ion doping concentration on near-infrared laser emission in lead borate glassy materials

Different concentrations (0.2–1.0 mol%) of Nd3+ doped lead borate glass (LB) systems were prepared by melt quenching technique and have been studied using XRD and optical studies. Based on the calculations of Judd-Ofelt (J-O) theory derived from the optical absorption spectra, three J-O parameters have been obtained. Various radiative parameters (such as radiative transition probability (Arad), branching ratio (βcal), absorption cross-sections (Σ), radiative lifetime (τR) and etc., have been predicted through J-O parameters. Luminescence spectra were measured for all the samples. It has been observed that luminesce intensity gradually increased up to 0.8 mol % of Nd3+ and further increase in concentrations causes that the luminescence spectral intensity falls. This is proposed due to the concentration quenching of neodymium ions in the LB glass system. LB glass system with 0.8 mol % is found to be most intensive one in emission at 1.06 μm related to 4F3/2→4I11/2 in near infrared (NIR) transition.

Improvement of mechanical properties and radiation shielding performance of AlBiBO3 glasses using yttria: An experimental investigation

Nuclear radiation shielding and rigidity parameters of the newly developed Al(0.1-x)B0.6Bi1.8O3Y2x glasses were studied to elucidate their potential as gamma radiation shielding material. In this study, bismuth borate glass systems with different amount of yttria additive were synthesized using melt-quenching technique. The material properties such as radiation shielding performance, structural and mechanical behaviors have changed with yttria additive into Bi-borate glasses. To obtain these changes, x-ray diffraction, scintillation gamma-ray spectrometer, and pulse-echo measurements have performed. The results showed that yttria additive has increased the density of glasses as well as radiation shielding performance. Also, the rigidity parameters were investigated not only experimentally but also theoretically. The results showed that G5 sample is superior nuclear radiation shielding sample with lowest HVL and MFP values. Moreover, yttria additive has increased the bridging oxygen atoms, enhances the coordination number as well as the cross-link density. The enhancement of all of these parameters indicates that these glasses are an excellent candidate to be used as a radiation shielding material. It can be concluded that yttria additive for aforementioned glass system has an important impact in mechanical and nuclear shielding properties yet further investigations should be considered for different types of applications.

Improved thermoluminescence and kinetic parameters of new strontium/copper co-doped lithium borate glass system

We report the modified thermoluminescence (TL) response of a new melt-quench synthesized strontium (Sr) doped lithium borate (LBSr) glass system co-doped with copper (Cu). Both Sr (0.5–2.5 mol%) and Cu (0.005–0.1 mol%) concentrations are varied to determine the optimum TL properties by exposing them to 6 and 10 MeV electrons irradiations. A single broad TL peak with the maximum peak temperature around 180–220 °C is evidenced. Glass sample with 2 mol% of Sr and 0.01 mol% of Cu content revealed the optimum TL response in addition to superior linearity in the dose range of 0.5–4 Gy. The dose dependent minimum detectable dose, fading, and reproducibility are determined. Samples displayed higher sensitivity to 10 MeV electron irradiations than to 6 MeV. Furthermore, this new composition showed easy annealing, excellent reproducibility, minimal fading and obeyed second order kinetics. These attractive features make the achieved glass system prospective for radiation dosimeter fabrication.

Study of environment friendly bismuth incorporated lithium borate glass system for structural, gamma-ray and fast neutron shielding properties.

The present work is aimed at incorporating the heavy metal oxide 'bismuth oxide' in lithium-borate glass system and studying its effect on the glass structure, durability, gamma-ray and neutron shielding ability. The density, XRD, Raman, FTIR, and UV-Visible spectroscopic techniques assisted in understanding the structure of ternary bismuth‑lithium-borate glass system. It has been found that the glass samples are of amorphous nature and structure is mainly built up of BO4, BO3, BiO6, BiO3 units and non-bridging oxygens (NBOs). Bismuth-incorporated glasses possess improved water resistance ability. The gamma-ray shielding ability was evaluated from mass attenuation coefficient, mean free path, tenth value layer and effective atomic number and it was found to be improved with the addition of bismuth oxide content. The exposure build up factor was also computed to account for the secondary photons and multiple Compton scattering. The removal cross section for fast neutrons (∑R) was also evaluated to study the neutron shielding ability of our prepared glasses. The glasses were also compared with barite concrete and commercial shielding glass RS 360 for gamma-rays and, with H2O, graphite, ordinary and hematite-serpentine concrete for checking neutrons shielding ability. It was observed that our glasses have better radiation shielding properties than the compared materials. In the light of these obtained results, it was concluded that the prepared bismuth‑lithium-borate glass system can be utilised for radiation shielding applications.

Effect of barium addition and plasma nitriding treatment on chemical and physical properties of Al, Pb borate glass system as a developed radiation shield

The effect of the BaO addition of to aluminum, lead borate in a series of (BaO)x (B2O3)60-x (Al2O3)10 (Li2O)10 (PbO)20 glasses where x = 0 to 50 weight% have been studied through their shielding, mechanical, thermal and chemical properties. The physical parameters such as molar volume (Vm), density (ρ), and oxygen packing density (OPD) were evaluated and discussed. Moreover, the thermal stability of the investigated system increases with BaO content. The present study proved that each of the plasma nitriding treatments of the samples and/or increasing Ba content greatly improved their ability to resist scratching and corrosion. Therefore, the obtained results are candidates for the present glass system to be effectively used as a protective shield against nuclear radiations in many advanced domains.

Investigation of gamma-ray shielding properties of bismuth borotellurite glasses using MCNPX code and XCOM program

Gamma-ray shielding properties of bismuth tellurium borate glass system doped with NdCl3 has a nominal composition of 65B2O3 − 12.5 Bi2O3 − 12.5TeO2 − (10 − x) Na2O − xNdCl3 (where 0 ≤ x ≤ 10 mol%) have been investigated. The mass attenuation coefficients (µ/ρ) for the present samples have been calculated at nine energy values (between 0.122 and 1.33 MeV) using the MCNPX code and XCOM program and the obtained data in the two methods were compared to check the accuracy in the MCNPX results. The results revealed that µ/ρ values gradually increase with the increase of NdCl3 from 0 to 10 mol%. The effective atomic number (Zeff), half value layer, and the mean free bath also were calculated. The results showed that the addition of NdCl3 in the present glass system improves the shielding performance of the B2O3–TeO2–Bi2O3–NdCl3–Na2O glass system against gamma radiation.

Structural and optical properties of samarium doped lithium lead borate glasses

Sm3+ doped LPB (lithium lead borate) glass system were synthesised by conventional melt quenching technique. The non-crystalline behaviour of the glass system were characterised by x-ray diffraction technique. The physical parameters of prepared glass sample such as inter-ionic distance, field strength, polaron radius, ion concentration, molar volume and density were calculated in reverse order starting with density using appropriate calculation technique. Simultaneous thermal analysis (STA) in the temperature range from RT to 850 °C. The FTIR spectra were recorded from 350 to 3500 cm−1 wavenumber range to study the functional group present in the sample. Raman spectra were recorded in the range of 650 to 1700 cm−1. From 220 nm to 1200 nm wavelength range were chosen to record the optical absorbance. The values of direct and indirect energy band gaps were calculated using the Tauc plot. Using optical band values and different methods, the refractive indices of the prepared glasses were calculated. The theoretical optical basicity, electronic polarizability and interaction parameter were calculated using the appropriate formulae. Luminescence spectra were recorded using 402 nm as the excitation wavelength. Sm3+ ion emits the strong orange colour at 599 nm, which seems to be useful for display device applications. The variation in different physical properties and optical properties of prepared glasses were discussed based on non-bridging oxygen and molecular weight of Sm3+ ions.

Multi-modal imageability and degradation characteristics of high-borate glass systems for transient embolization

Two glass series were developed based on the substitution of a monovalent glass modifier for a di- or trivalent ion in a high borate glass system. The BRS series consists of compositions 0.70 B2O3–0.30-X Rb2O – X SrO, and the BRG series consists of compositions 0.70 B2O3–0.30-X Rb2O – X Ga2O3, where 0.00 ≤ X ≤ 0.10 in increments of 0.2. All glasses were characterized in order to examine their composition-structure-property relationships, and to assess their potential for use as degradable, radiopaque embolic agents. Glasses were melt quenched, and evaluated in terms of structural changes (11B MAS-NMR, density, and glass transition temperature), changes in radiopacity (both CT and MRI), and changes in degradation timeframes under simulated physiological conditions. Structural analysis determined there was no change in the B4% of the BRS series, despite a linear increase in density and Tg. The strontium acts as a crosslinker, creating a more hydrolytically stable network, which leads to longer dissolution times. Conversely, the BRG series displayed a linear decrease in the B4%, a decrease in density (Tg data not available), yet a slight increase in hydrolytic stability is also observed. Gallium most likely acts more as a glass former than a glass modifier, thereby sequestering oxygens from the tetrahedral boron centers, creating trigonal B3 centers and tetrahedral gallium. All glasses were found to be imageable on CT (intensity > 3200 HU at 120 kVp), and invisible on clinical MR imaging modalities.

Effect of co-doping of lithium on the dosimetric properties of dysprosium-doped sodium borate glass system

The effect of lithium (Li) as a co-dopant on the Thermoluminescence (TL) properties of dysprosium-doped sodium borate (NB: Dy) exposed to two radiation sources (linear accelerator and Gamma-ray from Co-60) is reported in this study. The results showed an enhancement in the TL intensity with the increment of lithium to NB: Dy. Promising dosimetric properties were recorded; glow curve with simple and prominent peak, high signal stability and simple annealing process. Furthermore, the phosphor is reusable and high dose linearity range (up to 103 Gy). The current results propose the using of the new dosimeter in different dosimetric applications.

Statistical Mechanical Modeling of Borate Glass Structure and Topology: Prediction of Superstructural Units and Glass Transition Temperature.

Predicting the compositional evolution of the atomic-scale structure and properties of oxide glasses is important for designing new materials for advanced applications. A statistical mechanics-based approach has recently been applied to predict the composition-structure evolution in binary phosphate glasses, while topological constraint theory (TCT) has been applied in the last decade to predict the structure-property evolution in various oxide and nonoxide glass systems. In this work, we couple these two approaches to enable quantitative predictions of the compositional dependence of glass transition temperature and the population of superstructural units. The object of the study is the lithium borate glass system because they feature interesting structural characteristics (e.g., boron anomaly), and ample structure and property data are available. In these glasses, the average coordination number of boron first increases when lithium modifiers are added and then later decreases accompanied by network depolymerization. First, on the basis of 10B nuclear magnetic resonance spectroscopy data from literature, we present a statistical description of the structural evolution in lithium borate glasses by accounting for the relative enthalpic and entropic contributions to the bonding preferences. We show that the entire glass structure evolution (both short- and intermediate-range) can be predicted based on experimental structural information for only a few glass compositions. We then show that the developed structural model can be combined with a previously established TCT model to predict the compositional evolution of the glass transition temperature. This work thus opens a new avenue for the computational design of glasses with tailored properties.

Investigation of γ ray shielding, structural and dissolution rate studies of alkali based bismuth borate glass systems with MoO3 added

Abstract Bi2O3–B2O3–Li2O–K2O–MoO3 glass system has been synthesized using melt-quenching technique. γ ray shielding properties have been evaluated in terms of mass attenuation coefficient at photon energies 356, 662 and 1173 keV. These shielding parameters are also compared with standard nuclear radiation shielding material “barite concrete” at the same photon energies. Most of our prepared samples show better γ ray shielding properties as compared to barite concrete at the same photon energies. Density, molar volume, XRD, FTIR and Raman studies have been employed to study the structural properties of the prepared glass system. Different structural groups such as [BO3], [BO4], [MoO4] and [MoO6] have been detected in the amorphous network. The presence of non-bridging oxygens, bridging oxygens and change of coordination number has been discussed. The optical absorption spectra are recorded in the wavelength range 200–800 nm and optical band gap is calculated which has shown strong dependence on Bi2O3/B2O3 ratio. The samples have also been tested for their durability by measuring dissolution rate properties using distilled water at 90°C. It has been concluded that increase in the content of Bi2O3 in the composition improves durability and γ ray shielding properties of the samples.