Lead Borosilicate Research Articles

Impact of Bi2O3 on the Structural, Optical, Radiation Shielding, and Dielectric Analysis of Lead Borosilicate Glasses Doped with TiO2

Objective: The principal aim of this investigation was to assess the impact of bismuth oxide on the optical properties, radiation shielding characteristics, and dielectric behavior of lead borosilicate glasses doped with titanium oxide at a low concentration. Method: We intended to utilize the conventional rapid melt quenching method to produce glasses with the following chemical composition: 25 PbO+ 15 B2O3 + 0.1 TiO2 + (59.9-x) SiO2 : x Bi2O3(0≤x≤12). Findings: XRD and SEM analyses were used to confirm the samples' non-crystalline properties, while DTA investigations were used to evaluate the samples' ability to form glass. The numerous structural elements were identified through the utilization of FT–IR and Raman analyses. The optical characteristics of glasses are determined by optical absorption studies. The findings derived from optical absorption spectral analyses revealed a progressive increase in the concentration of octahedral Ti4+ ions with the mol% Bi2O3 concentration. In order to analyse the glasses' dielectric properties, an impudence analyser was employed. The results obtained from these inquiries indicate that glasses do contain Bi2O3 at concentrations lower than 12 mol% experience a progressive increase in dielectric constant values. Further investigation is conducted into the radiation shielding properties of the glasses. Novelty: The findings indicate that the values of the glasses' optical band gap, radiation shielding ability, dielectric constant, and thermal stability are all directly correlated with their Bi2O3 concentration. Keywords: FT­IR, Raman, OBG, MAC, Activation Energy

Characterization of a Novel System of Bismuth Lead Borosilicate Glass Containing Copper

Objectives: The primary objective of the present investigation was to examine the impact of Bi3+ ions on the optical, radiation shielding, dielectric and structural characteristics of lead borosilicate glasses doped with CuO. Method: In this view, we planned to utilize the conventional rapid melt quenching method to produce glasses with the following chemical composition: 25 PbO + 15 B2O3 + 0.1 CuO + (59.9-x) SiO2 :x Bi2O3 (0≤x≤12). Findings: The samples' non-crystalline characteristics were validated through XRD and SEM analysis, respectively, while their glass-forming capabilities were assessed through DTA studies. Utilizing the FT–IR and Raman analyses, the numerous structural units were determined. According to the findings of the FT-IR, and Raman analyses, the degree of disorder in the glass network increased. By means of optical absorption experiments, the optical properties of glasses were determined. The results obtained from optical absorption spectral investigations indicated that the concentration of octahedral Cu2+ ions increased gradually as the Bi2O3 concentration increased to 12 mol %. The dielectric properties of the glasses, suggested that the dielectric constant values of glasses containing Bi2O3 in concentrations below 12 mol% increase gradually. Additionally, the radiation shielding properties of the glasses are investigated. The values of radiation protection ability found to be purely function of Bi2O3 concentration. Novelty: The results suggest that the glasses' thermal stability, dielectric constant, optical band gap and radiation shielding ability values purely function of Bi2O3 concentration. Keywords: Borosilicate glasses, Thermal stability, Optical absorption, Radiation shielding properties, Dielectricsq

Immobilization of Technetium-99 in a Lead Borosilicate Glass

The volatility of Technetium-99 (99Tc) makes vitrification of Tc-containing nuclear waste at high temperatures a challenge. In this paper, we report the development of a lead borosilicate glass with a nominal composition of 73.1PbO–10.1B2O3–13.1SiO2–3.7Al2O3 (wt%) and a depressed melting temperature (750 °C) to decrease Tc volatilization during vitrification. The lead borosilicate glass was able to incorporate up to ∼1.8 wt% Re (as a surrogate for 99Tc), and the results of a product consistency test showed that it was chemical durable. Raman and Fourier transform infrared spectra showed that Re was incorporated into the lead borosilicate network as ReO4− and the small addition of Re did not induce any detectable changes to the B and Si network. At the same time, nuclear magnetic resonance measurements suggested that some of the ionic Pb in the glass turned to covalent Pb with the addition of KReO4. No loss of Re was detected when vitrification of the Re-containing lead borosilicate glass was conducted at 750 °C, and only ∼12% of the Re volatilized when the temperature was ramped up to 1100 °C. Our findings confirm suggestions that lead borosilicate glass would be an attractive candidate waste form for immobilizing Tc concentrate.

Impact of Gd3+ on Optical, Local Structure, and Attenuation Properties of Lead Borosilicate Glasses

Impact of Gd3+ on Optical, Local Structure, and Attenuation Properties of Lead Borosilicate Glasses

Prediction of the Judd–Ofelt Parameters of Dy3+-Doped Lead Borosilicate Using Artificial Neural Network

Developments in the field of glass research necessitate the mimicking of the optical properties of glass materials before melting the raw materials, as they are very expensive nowadays. An artificial neural network (ANN) was utilized during this work to train and predict the Judd–Ofelt parameters of various glasses, such as Ω2, Ω4 and Ω6, and the radiative lifetimes of many different types of rare-earth-doped glasses. The optimized ANN architecture for forecasting the Judd–Ofelt parameters were found to be very near to the experimentally measured parameters. Then, the conferred ANN model was employed to predict the Judd–Ofelt parameters of some newly prepared borosilicate glasses. Therein, a new glass system of 0.25 PbO–0.2 SiO2–(0.55 − x) B2O3–x Dy2O3, was prepared in order to employ the melt-quenching technique. The parameter results of the Judd–Ofelt theory, as well as the Ω2, Ω4 and Ω6 and radiative lifetimes showed that the supplementation of Dy2O3 switched the BO4 units to BO3 units with oxygens that were non-bridging atoms, thus weakening the glass frameworks. Therefore, it is very important to use an ANN to predict the Judd–Ofelt parameters of several rare-earth-doped glasses as luminescent materials.

Reduction in contact resistivity of Ag thick-film conductor on SiNx-coated Si wafer for solar cell using lead tellurite glass frit

In an application for metallization contact of Ag thick-film conductor onto the SiNx-coated Si wafer for solar cells, we examined the wettability, reactivity, microstructure, and electrical contact of two kinds of glass frits: lead borosilicate and lead tellurite. The lead tellurite frit exhibited superior wettability on Si and higher reactivity with SiNx and formed the thinner glass layer between Ag rich layer and Si for firing the Ag thick-film paste at 750 °C, resulting in better conductive contacts. The contact resistivity of Ag thick-film conductor using lead tellurite glass frit was less than one-tenth of that using lead borosilicate glass frit.

Comparative Studies on Polarizability, Optical Basicity and Optical Properties of Lead Borosilicate Modified with Titania

The authors reported the data found by FT-IR spectroscopy, ultrasonic velocities, DTA and, optical investigations of (50-x) Na2B4O7–30PbO2–20SiO2–xTiO2 where x = (0, 10, 20, 30, 40, and 45) mol%. The structure changes of these glasses will be studying by FT-IR spectra. The mechanical properties have been associated with the results of FT-IR spectra. It was noted that the ultrasonic velocities, elastic-moduli, and density physical properties of these samples increased. The obtained results will discuss in terms of structural changes due to the addition of TiO2. Optical feature spectra are recorded at room temperature. The Urbach’s energy (Eu) of the prepared samples has been estimated. Polarizability and basicity of the prepared glasses according to the refractive index and optical bandgap have been investigated. The nature of the produced glasses and glass–ceramics was examined by (XRD) analysis.

Thermal properties and stability of Catalan Modernist blue and green enamels

AbstractStained glass is a fragile component of our Cultural Heritage. In particular, the stained glass produced during the last decades of the 19th century and first decades of the 20th century is characterised by the use of a new type ready‐to‐use enamels. Stained glass was used for the windows of buildings, and a large part of it is exposed to weathering and consequently to deterioration. This study analyses the collection of materials used in one of the most important stained glass Modernist workshops in Barcelona. The chemical composition is determined (and pigments identified) by means of Laser Ablation Inductively‐Coupled Plasma Mass Spectrometry and X‐Ray Diffraction and the thermal properties of the enamels measured by Differential Scanning Calorimetry and Hot Stage Microscopy. The enamels are made of a lead‐zinc borosilicate glass characterised by its low sintering temperatures and high stability against chemical corrosion, in particular to water corrosion. However, the relatively narrow range of firing temperatures necessary for correct adherence of the enamels to the contemporary glass base may have required the addition of a high lead borosilicate flux, which would have increased the lead content of the enamel, decreasing the firing temperature but also its stability.

Phase separation of cesium from lead borosilicate glass by heat treatment under a reducing atmosphere

A phase-separation technique for removing sodium from glass using a heat-treatment method under a reducing atmosphere was previously developed for sodium recovery from waste glass. In this study, this technique was applied to cesium-containing lead borosilicate glass to concentrate the cesium in phase-separated sodium-rich materials for efficient cesium extraction. The theoretical phase-separation temperature of the sodium-rich phase was simulated by thermodynamic equilibrium calculations and was predicted to occur below 700°C for lead borosilicate glass. Experimentally, a simulated lead borosilicate glass was melted at 1000°C and subsequently annealed below 700°C under a CO-containing reducing atmosphere. The phase separation of cesium was found to occur with sodium enrichment on the glass surface that was in contact with the gas phase, promoting cesium extraction from the treated glass using water. The cesium extraction efficiency was affected by the surface area of the treated glass that was in contact with water, and under the examined conditions, the cesium extraction efficiency was up to 66%. Phase separation using reductive heat treatment, combined with a water leaching technique, is suggested to be effective for extracting cesium incorporated in borosilicate glass waste.

Effect of Dy3+ ions concentration on optical properties of lead borosilicate glasses for white light emission

Lead borosilicate (LBS) glasses doped with different concentrations of Dy3+ ions (0.1, 0.5, 1.0 and 2.0 mol%) were synthesized by the conventional melt quenching method. The prepared glasses were characterized through X-ray diffraction (XRD), optical absorption and photoluminescence spectra. The glassy nature of LBS host glass has been confirmed from XRD analysis and the Judd–Ofelt (JO) intensity parameters (Ωλ, λ = 2, 4 and 6) have been calculated from the intensities absorption bands. The evaluated parameters are then used to calculate radiative properties such as radiative transition probabilities (AR), total transition probability (AT), radiative lifetime (τR) and branching ratios (βR) for the excited 4F9/2 level of Dy3+ ions. From the emission spectra, the effective band widths (Δλeff), stimulated emission cross-sections (σ(λp)), yellow to blue (Y/B) intensity ratios, experimental lifetimes (τexp) of 4F9/2 metastable state and the chromaticity color coordinates for white light emission have been determined and discussed.

Current Transport Through Lead–Borosilicate Interfacial Glass Layers at the Screen–Printed Silver-Silicon Front Contact

During the firing of screen-printed silver contacts in industrial crystalline silicon solar cells, an interfacial glass layer is formed between the silver bulk contact and the silicon substrate. By means of numerical modeling, we investigate conduction mechanisms across the interfacial glass layer, which consists of lead–borosilicate glass enclosing silver colloids. As there is a considerable lack of parameters for the interfacial glass layer, we revisit properties of similar materials such as as-grown crystalline and polycrystalline lead monoxide. We revise characteristics of applications that use similar glasses, such as photodetectors, thick-film transistors, and surface passivation. We propose that current transport via the interfacial glass is similar to the one in thick-film resistors based on ruthenium-doped lead–borosilicate glass. Device simulations are performed using direct tunneling, trap-assisted tunneling, and a conducting insulator model for current transport across the interfacial glass layer. The tunneling mechanisms are only effective for thin interfacial glass layers up to 2 nm. A combination of direct tunneling and the conducting insulator modeling is well suited to model interfacial glass layers between 0.5 and 1000 nm. Applications to specific contact resistance measurements show that the resistivity of the interfacial glass is in the range of thick-film resistors of similar lead monoxide content.

Analysis of the luminescent spectra of Eu3+ in glasses

The spectroscopy properties of lanthanide ions in glasses differ remarkably from crystal and powder samples due to superposition of transitions from many ions with different local environments. Eu3+ ions were doped in lead–borosilicate and boro–tellurite glass samples to probe the structural information and to reveal their effects on the luminescent properties of lanthanide ions. Three emission peaks were observed for 5D0→7F0 transition, with peak energies linearly dependent on the excitation wavelengths, and correlation between the intensity ratio of 5D0→7F0 versus 5D0→7F2 and the width of 7F1 was observed. The former indicates that there are three subsets of Eu3+ sites in the samples, with 7F0 being pushed downwards by 7FJ (J=2, 4, and 6) by crystal-field J-mixing, and the latter can be quantitatively modeled by the adaptation of the theoretical model of Wen et al. [Phys. Chem. Chem. Phys. 12, 9933 (2010)] to account for the corrections due to the inhomogeneous broadening of 7FJ (J=0, and1) crystal-field levels. The methods explored here can be applied to study other glass hosts for luminescent materials.

Transport properties of microwave sintered pure and glass added MgCuZn ferrites

Abstract A series of pure stoichiometric and 1 wt% lead borosilicate (PBS) glass added MgCuZn ferrite with the general formula Mg 0.5 Cu x Zn 0.5− x Fe 2 O 4 with x = 0.05, 0.1, 0.15, 0.2, 0.25 and 0.3 were synthesized by microwave sintering technique. Single phase spinel structure is exhibited by the XRD patterns of these ferrites. DC and AC conductivity were investigated as a function of composition, temperature and frequency. DC conductivities were also estimated using the impedance spectroscopy analysis of Cole–Cole plots. The DC conductivities thus obtained are in good agreement with the experimental results. All the investigated samples exhibited two regions of conductivity one in the low temperature and the second in the high temperature region. It is observed that PBS glass added samples have lower conductivities than pure samples. Due to their lower conductivities and sintering temperatures the 1 wt% PBS glass added samples are suitable for multilayer chip inductor (MLCI) and high definition TV deflection yoke material application.

Role of aluminium oxide in the structure of heavy metal oxide borosilicate glasses

AbstractLead borosilicate and bismuth borosilicate glasses with and without aluminium oxide of varying compositions were prepared by conventional melt‐quench method. Raman spectroscopy was used to analyze the influence of Al2O3 incorporation in the heavy metal oxide borosilicate glass network. The compositions of glasses were chosen in a way that Al2O3 is added at expenses of PbO and Bi2O3 in lead borosilicate and bismuth borosilicate glasses, respectively.

Dependence of the surface generation velocity at silicon-(lead borosilicate) glass interface on conditions of nonequilibrium depletion region formation

The generation characteristics of silicon-(lead borosilicate) glass interface have been studied by the method of isothermal capacitance transient spectroscopy in the metal-insulator-semiconductor (MIS) structure. It is established that the effective surface generation velocity depends on the amplitude of the inverting voltage pulse that drives the MIS structure out of the equilibrium state. The observed dependence may be caused by the injection of charge carriers through the silicon-glass interface followed by their localization on traps in the region of glass near the interface.

Fabrication of glassy ceramic membrane filters for filtration of spring water with clogging phenomena

Ceramic membrane filters consisting of a filtration layer of varying thickness coated on a tubular porous support made of quartz-based materials and with a pore size of about 10 μm were fabricated. The filtration performance for spring water clarity was examined. The coatings were prepared by a filtration process with a dilute particle suspension of quartz-natural zeolite–lead borosilicate glass mixture. The filter matrix was of quartz type and the additives (frit glass and zeolite) made the filters with glassy pore walls as the sintering temperature applied was above their fusion temperature. The pores of the filtration layer have a relatively coarse size distribution and thus lead to clogging phenomena within the glassy pores during filtration operation. The pore clogging is a benefit for producing clear filtrate and the glassy pore walls favour the filter cleaning and recovery. It was observed that a sufficiently thick coating (>62 μm) was required for good enough filtrate clarity (0.2 NTU turbidity) and cleaning of the filter was possible by filtrate backflushing and air blowing.

Physical Properties of Barrier Ribs of Plasma Display Panels: I, Formation of Pores during Sintering of Lead Borosilicate Glass Frits

The effects of chemical compositions on the sintering behavior and physical properties of lead borosilicate glass developed for barrier ribs of plasma display panels (PDP) were investigated. The formation of pores during sintering of the glass was noted, and their formation mechanism was investigated using XPS, TG/DTA, and XRD. A change in the oxidation state of the lead was discussed as a possible cause for the formation of pores in the sintered samples.

Lead Borosilicate Glass Frit의 소결시 기공의 형성 기구

Effects of chemical compositions on the sintering behavior of the lead borosilicate glass developed for barrier ribs of plasma display panels were investigated in this study. Formation of pores during sintering of the glass was noted and their formation mechanism was investigated using XPS, TG/DTA, and XRD. The results indicated that pores are formed by the oxygen released from Pb-oxides during sintering.

Properties of Passivating Coatings Based on Lead Borosilicate Glass

The charge distribution in passivating coatings based on lead borosilicate glass was studied by temperature-dependent flat-band voltage measurements. The results indicate the presence of two types of charge in the interfacial layer of the glass: a temperature-independent negative charge and a variable positive charge, which increases with temperature. The variable charge is shown to be associated with the donor states present in the interfacial layer, which exchange electrons with the semiconductor bulk.

Analysis of the structure of lead borosilicate glasses using laser ionization time of flight mass spectroscopy

We report on high resolution laser ionization time-of-flight mass spectroscopy (LITOF-MS) measurements of lead borosilicate and sodium-doped lead borosilicate glasses. This technique permits the observation of intermediate range mesounits, and provides new insights into the glass network structure. In lead borosilicates we observed strong mixing of borate and silicate groupings, a likely absence of diborate units, and the formation of boroxol rings with one lead cation (PbB 3O 6) at borate-rich compositions. The spectra also suggest the growth of a limited lead oxide subnetwork at high Pb contents. In the sodium-doped glasses we see a preference of the sodium for boron units, and the simultaneous appearance of sodium-containing silicate units between 10 and 24 mol% Na 2O, though borate association remains predominant. The reedmergnerite unit (BSi 4O 10) is seen in very small amounts in both glass families.