Phosphate Glass Samples Research Articles

Investigation of structural, optical characteristics of Gd3+ doped phosphate glass for radiation shielding applications

Gadolinium doped phosphate glass was created with a composition of 70 P2O5 + 5Al2O3 + 5 Ba2CO3 + 9 KF2 + 5 MnO2 + 5 SnO+1 Gd2O3 by using the melt-quenching process. The prepared glass sample’s amorphous nature was confirmed by the X-ray diffraction analysis. FT-IR examination confirms the presence of phosphate functional groups. Glass’s optical band gap was found to be 3.5 eV using Tauc’s plot method. The photoluminescence analysis indicates that the emission band at around 311 nm. The Commission International de I’Eclairage (CIE) was employed. It was identified that the computed chromaticity coordinate values (x = 0.3164 and y = 0.3371) were situated in the summer sunlight zone, close to the white light region. The attenuation capabilities of the gadolinium-doped phosphate glass sample were validated by the gamma ray shielding parameters. The mass attenuation coefficient and Mean free path of the prepared glass were fund to be 4.41 × 105 cm2/g at 0.015 MeV and 12.4 cm at 15 MeV respectively. In terms of infiltration deepness up to 40 MFP, the energy-related energy buildup factor (EBF) and energy absorption buildup factor (EABF) of glasses were calculated using the five (a, b, c, d, and Xk) parameters of the G-P fitting scheme. All of the results show that the synthetic glass can be used as shielding materials against gamma radiation.

Gamma-Ray Sensing Properties of Nd Doped Phosphate Glasses

Five selected Nd2O3 doped phosphate glass compositions are synthesized using melt quench technique. The physical properties such as density (ρ) and molar volume (Vm) are experimentally measured. The density increases whereas molar volume decreases with addition of Nd2O3 content. The radiation sensing properties for these rare earth (RE) element doped phosphate glass samples have been investigated. The photon attenuation and sensing parameters such as mass attenuation coefficient (μm), linear attenuation coefficient (μL), optimum thickness range (x opt), effective atomic number (Zeff), and mean free path (mfp) values are computed over wide gamma-ray energy range 1keV -100 GeV within framework of WinXCom software tool. The photon sensing properties of these rare earth doped phosphate glasses vary significantly on account of neodymium oxide content and photon energy. The mean free path (mfp) values of glass samples are found to decrease while the mass attenuation coefficient values rise as Nd2O3 concentration does.

Enhanced linear and nonlinear optical properties of erbium/ytterbium lead phosphate glass by gamma irradiation for optoelectronics applications

Herein, this study intends to reveal the impact of gamma irradiation on the structural, linear, and nonlinear optical characteristics of 47P2O5−23Na2O−6Al2O3−22PbO−0.5Er2O3−1.5Yb2O3 glass. The Er/Yb-doped lead phosphate glass samples were produced using the traditional melt quenching procedure and then treated to different doses of gamma irradiation (0, 20, 50, and 100) kGy. The amorphous phase structure of the Er/Yb-doped lead phosphate glass samples was verified through XRD patterns. Also, the shift of the FTIR peaks due to the change in bond angles, and the change in the bond length of the P–O–P bridges means the glass network stability against radiation. With increasing irradiation dosages, the energy gap dropped from 4.11 eV to 3.42 eV and then enhanced to 3.48 at 100 kGy. At the same time, the Urbach energy enhanced from 10.23 eV to 37.03 eV. The oscillator energy Eo was found between 1.55 and 1.62 eV. Also, the dispersion energy Ed varied between 2.11 eV at 100 kGy and 2.71 eV at the dose of 50 kGy. The percentage of free carrier ions to effective mass (N/m*) is in the range (4.82–8.66) × 1047 cm3/g. Besides, the lattice dielectric constant ({varepsilon }_{l}) increased from 5.54 to 6.63 as the gamma dosages increased. Furthermore, increasing gamma doses up to 50 kGy promotes susceptibility, which subsequently declines at 100 kGy, suggesting that increasing gamma doses over 50 kGy weakens polarizability potential. While the increasing gamma doses up to 50 kGy reduces the nonlinear refractive index and then improves at 100 kGy. Overall, the nonlinear and linear research revealed that Er/Yb lead phosphate glass is being used as a promising material for gain media and optical amplifiers.

Investigation of spectroscopic properties of Sm3+ doped phosphate glasses for reddish orange light applications

Samples of phosphate glasses with composition of (40-x) P2O5-40Na2O-20ZnO-xSm2O3, with Sm3+ ion concentration varying from 0.1 to 2.5%, were synthesized using melt quenching technique and characterized by X-Rays Diffraction, UV–Vis and luminescence spectroscopies. Using Judd-Ofelt analysis, the parameters Ω2, Ω4 and Ω6 of Sm3+ (4f7) were determined. Three transitions of Sm3+: 4G5/2→ 6H5/2, 6H7/2, 6H9/2 were observed from the luminescence spectra. The radiative (τr) and the measured (τmea) lifetimes for 4G5/2 level, were discussed and compared with other works. The quantum efficiency (η) is found to be higher for × = 0.5 mol % of Sm2O3. The CIE chromaticity coordinates were calculated, and it was found that PSm glasses can be suitable for the development of visible lasers in the orange red spectral region.

Structural studies on varied concentrations of europium doped strontium phosphate glasses

In this study, the conventional melt quenching method was used to prepare pure and the europium-doped strontium phosphate-based glasses. This study aims to discover the effect of the europium content on the structural properties of synthesized glasses. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) absorption spectra were employed to examine the structural characterization of these prepared samples. XRD analysis shows that all samples of undoped and europium-doped phosphate glasses have amorphous phases. The FTIR absorption spectra demonstrated that various structural phosphate groups have been represented in the synthesized samples. The europium-doped strontium phosphate glasses can be used in many applications such as laser, optoelectronics, LED display, solar cells, and photonic devices. [Copyright information to be updated in production process].

Use of Terbium Doped Phosphate Glasses for High Dose Radiation Dosimetry—Thermoluminescence Characteristics, Dose Response and Optimization of Readout Method

The phosphate glass samples doped with Tb2O3 oxide (general formula: P2O5-Al2O3-Na2O-Tb2O3) were synthesized and studied for usage in high-dose radiation dosimetry (for example, in high-activity nuclear waste disposals). The influence of terbium concentration on thermoluminescent (TL) signals was analyzed. TL properties of glasses were investigated using various experimental techniques such as direct measurements of TL response vs. radiation dose, Tmax–Tstop and VHR (various heating rate) methods, and glow curve deconvolution analysis. The thermoluminescence dosimetry (TLD) technique was used as the main investigation tool to study detectors’ dose responses. It has been proved that increasing the concentration of terbium oxide in glass matrices significantly increases the thermoluminescence yield of examined material. For the highest dose range (up to 35 kGy), the dependence of the integrated thermoluminescent signals vs. dose can be considered as a saturation-type curve. Additional preheating of samples improves linearity of signal vs. dose dependencies and leads to a decrease of the signal loss over time. All obtained data suggest that investigated material can be used in high-dose radiation dosimetry. Additional advantages of the investigated dosimetric system are its potential ability to re-use the same dosimeters multiple times and the fact that reading dosimeters only requires usage of a basic TL reader without any modifications.

Effect of alkaline earth metals on luminescence characteristic in Eu-Doped oxynitride phosphate glasses

In this article, a series of Eu-doped oxynitride phosphate glass samples are prepared. It is shown that the photoluminescence of Eu can be tuned through different alkaline earth metal ions (M2+). The luminous intensity of Eu2+ decreases with increasing ionic radius in the order of Mg＜Ca＜Sr＜Ba. And with the increased mismatch degree of radius between M2+ and Eu ions, the luminescence of Eu3+ gains intensity. The effects of M2+ on structure and luminescence characteristics of glass are mainly due to the following three factors: the field strength of M2+, the degree of mismatch between M2+ and Eu ions, and the influence of alkaline earth metals on the coordination tendency of N3− and O2− with Eu ions. The reduction mechanism is explained by combining the unequal substitution of Eu3+ ions for divalent alkaline earth metal cations with the reduction of Eu3+ by O2− and N3− ions. Our work provides a new perspective for studying the luminescence characteristics and mechanism of Eu ions in oxynitride Phosphate Glasses.

Comparative Study of Er3+ Ions Doped Phosphate Based Oxide and Oxy-fluoride Glasses for Lasers Applications

Abstract Er3+ ions doped sodium strontium gadolinium oxide and oxy-fluoride phosphate glass samples prepared by conventional melt quenching technique. The samples were melted at 1200 °C in electric furnace with alumina crucibles. The densities of the samples were measure with the help of Archimedes principle using water as immersion liquid. The refractive index (n) was measured by Abbe refractometer with a sodium-vapour lamp as a light source and using mono-bromonaphthalene (C10H7Br) as a contact liquid. The prepared glass samples were characterized with UV-Vis-NIR absorptions and NIR photoluminescence. The UV-Vis-NIR spectra show peaks at 379, 406, 488, 521, 548, 652, 803, 977, and 1536 nm which are due to the transitions from 4 I15/2 ground state to 2H9/2, 4F3/2, 4F7/2, 4H11/2, 4S3/2, 4F9/2, 4I11/2 and 4I13/2 exited states of Er3+ ions, respectively. In NIR emission one broad peak at 1543 nm is observed in present glass samples with 379 nm excitation. From NIR emission it is observed that the FFEr glass give better emission intensity than the GEr and FEr. McCumber theory was used to evaluate stimulated emission cross-section of 4I13/2→4I15/2 transition of Er3+ ion using the absorption spectral measurements. Thus, these results show that present glasses have the potential for use in efficient short and conventional-length optical amplifiers and tuneable lasers

Plasma spectroscopy + chemometrics: An ideal approach for the spectrochemical analysis of iron phosphate glass samples

AbstractThe penultimate aim of all analytical techniques is to provide best quantitative information with high sensitivity and accuracy. Such techniques then can be ideal to estimate the concentration of different species in a sample or to measure the surface concentration and so on. The preliminary step involved in quantitative analysis is evaluation of the system response for a given amount of the analyte under investigation. Different methodologies are proposed and executed for the above mentioned purpose. In this work, we have demonstrated the performance of chemometric methods to study the atomic emissions from simulated nuclear waste glasses. Five samples of iron‐phosphate glasses were synthesized by doping Cr, Sr, and Ti at various concentrations. The spectra recorded using laser‐induced breakdown spectroscopy (LIBS) system were analyzed using principal component analysis (PCA), partial least square‐discriminant analysis (PLS‐DA), and support vector machines (SVM) for the classification. As compared with the PLS‐DA, SVM provided better results for classification with accuracy of 100% on both calibration and validation sets, respectively. The quantitative analysis of glass samples is carried out using partial least square regression (PLSR) and support vector regression (SVR). The root mean squared error of prediction (RMSEP) is found to be 0.16, 0.20, and 0.08 (wt%) for Cr, Sr, and Ti using PLSR. The detailed investigation elucidates the advantages of chemometrics in handling the complex LIBS spectrum of glass samples and their significance in process control of nuclear waste, nuclear forensics, and so on.

XAFS analysis of ruthenium in simulated iron phosphate radioactive waste glass

The chemical state of ruthenium in simulated iron phosphate radioactive waste glass was investigated by conventional X-ray absorption fine structure (XAFS) and imaging XAFS analyses. The EXAFS analysis suggested that ruthenium was contained as glass phase when content of the waste components was less than 10 wt.% in 30 mol%Fe2O3-P2O5 base glass. In other samples, crystalline RuO2 was observed and became prominent with the increase of waste content. According to the imaging XAFS analysis, RuO2 particles in all samples had length smaller than 50 μm. Large size aggregations of RuO2, which are found frequently in nuclear waste borosilicate glass, were not seen in any of the iron phosphate glass samples.

Influence of (Er3+, La3+, Ce4+) additions on physical and optical properties of 50CaO–50P2O5 glasses

Calcium phosphate glass samples with the addition of 5 mol% of three different rare earth oxides (Erbium, Lanthanum and Cerium oxides) were made by melt quenching process. Effect of rare earth ions addition on structural, physical and optical properties has been investigated using density measurement, XRD diffraction, Fourier transformed infrared (FTIR) spectroscopy, ultra violet visible spectroscopy and Abbe Refractometer. The random short range order of synthesized glass samples was analyzed by XRD diffraction. The absorption spectra have been recorded and optical band gap energy was determined by using Tauc plotting. The band gap energy showed a decrease when 5 mol% of rare earth (Er2O3, La2O3, and CeO2) oxides were added to the host glass. Fourier transformed infrared (FTIR) spectrometer was applied to study the structural changes of the synthesized glasses. The density and refractive index of synthesized glasses was measured and related parameters were calculated. These values are compared with the un-doped metaphosphate glass. Based on measured density, the concentrations of added rare-earth ion is calculated. With an increase in ion concentration, the internuclear distance decreased leading to an increase in field strength.

Investigations of the kinetic energy parameters of irradiated (La)-doped phosphate glass.

The current study characterizes and analyzes glow curves obtained from phosphate glass doped with different concentrations of lanthanum. Kinetic parameters of the glow curves obtained from beta-irradiated phosphate glass samples doped with lanthanum were determined using a newly designed deconvoluted software. The obtained results from the analyses indicated that the glow curves of the phosphate glass samples were composed of five overlapping peaks. The activation energies of the five electron traps were located between 0.622 and 1.133eV. The obtained kinetic parameters were evaluated using the designed software and another two methods and all revealed good agreement. The first three traps displayed non-first-order behaviour, while the two deep traps obeyed nearly first-order kinetics.

The effective contribution of PbO on nuclear shielding properties of xPbO-(100 − x)P2O5 glass system: a broad range investigation

The radiation shielding properties for glass system with the composition of xPbO-(100 − x)P2O5 (5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 mol%) were studied. For that purpose, 3 × 3 inch NaI(Tl) scintillation detector was designed to detect the photons using simulation code of MCNPX program. Consequently, the mass attenuation coefficients (μ/ρ) were calculated. The predestined (μ/ρ) values using MCNPX code for twelve glass samples were checked together with the XMuDat and XCOM software outcomes. The half value layer (HVL), proton mass stopping power (MSP), exposure buildup factor (EBF) and proton projected range were estimated in a broad energy zone of 0.015–15 MeV. In addition, the neutron radiation shielding parameters i.e. mass removal cross section for neutron (∑R), Coherent neutron scattering length (bco), incoherent neutron scattering length (binc), coherent neutron scattering cross section (σco), incoherent neutron scattering cross section (σinc), total neutron scattering cross section (σtot) and absorption neutron scattering cross section (σabs) of glasses were computed. The addition of PbO has an impact on the radiation protection properties of phosphate glass systems improve the radiation shielding properties of phosphate glass samples, where (μ/ρ), ∑R and effective atomic number (Zeff) values increase when the chemical composition of lead oxide increase while HVL, EBF MSP and projected range values decrease. That underlines our research in that way that it appears that the addition of lead oxide has an impact on the radiation protection properties of phosphate glass systems.

Antifouling effect of water-soluble phosphate glass frit for filtration plants.

The antifouling, antimicrobial, elution behavior, skin irritant, and cytotoxicity properties of water-soluble phosphate glass on stainless steel were evaluated. Water-soluble phosphate glass samples with 35% Cu (mol/mol) were prepared by altering the network modifier (Na2O, K2O) and network former (P2O5, B2O3) compositions. The materials were melted at temperatures within the range of 850-950°C. The melt was then quenched and ground into fine particles using a twin roll mill. The resulting water-soluble glasses were prepared as glass frit (size < 100μm) using a sieve. The amorphous phase was determined by X-ray diffraction and differential thermal analysis. Water-soluble glasses with a reduced Cu ion elution rate of 1.2ppm per week were formed because the chemical resistances of the formulated glasses improved as the P2O5 content decreased and the B2O3 content increased. To test its antifouling properties, the glass frit was mixed with paint and coated onto a STS316L sheet. The surface roughness was increased markedly from 1.4 to 19.2nm, increasing the specific surface area for antimicrobial activity. It was demonstrated that the proposed method was able to form noncytotoxic, nonirritant, water-soluble glasses with 99.9% antimicrobial activity against Staphylococcus aureus. These results suggest that water-soluble phosphate glass on STS316L sheets could be useful in filtration plants.

Thermoluminescence characteristics and dose response of electron beam and gamma rays irradiated alumino-phosphate glasses doped with Gd2O3 and Tb2O3

Phosphate glass samples doped with Gd2O3 and Tb2O3 oxides were synthesized and studied towards potential application in high dose radiation measurements. Glass/polytetrafluoroethylene composite detectors were prepared and used to study dosimetric signal dependencies, and thermoluminescence dosimetry (TLD) technique was used as a main investigation tool to study detectors response. Influence of dopants and polymer on TL signal were investigated. The dosimetric properties, like dose response, linearity and signal stability of the composite dosimeters were investigated. Incorporation of lanthanide oxides into glass matrix changes substantially the thermoluminescent behavior of phosphate glass. The highest luminescence yield exhibits glass doped with terbium oxide. Negligible influence of polytetrafluoroethylene agglutinator on dosimetric signal was observed. Dependence of the integrated thermoluminescent signals for all samples vs. absorbed dose can be considered as linear. The new phosphate glass-polytetrafluoroethylene composites show good material and thermoluminescent properties for the high gamma and electron beam dose measurement applications.

Study of stress-induced birefringence in an inhomogeneously pumped laser rod with spatial and temporal resolution

A general method to study the birefringence induced under laser pumping is presented. The method was tested on an Nd:Phosphate glass sample that is transversally and inhomogeneously pumped by a pulsed laser diode. Measurements to resolve the spatial and temporal stress-induced birefringence distribution are compared to a numerical model simulating the experimental setup. A quantitative agreement between measurement and simulation was found, showing that unmeasurable physical processes can be known in general cases. To compare the measurement and the simulation, a new formalism to extract the induced birefringence from initial and total birefringence measurement is presented.

Influence of Er3+ ions on the physical, structural, optical, and thermal properties of ZnO–Li2O–P2O5 glasses

Er3+ doped zinc lithium phosphate glass samples were synthesized by the very simple melt quenching method. The obtained X-ray diffraction patterns specify that the prepared glass samples exhibit glassy nature. The physical properties like packing density, molar volume, density, oxygen packing density, interionic distance, field strength, rare earth ion concentration, and polaron radius were calculated using appropriate formulae. DTA curve was analysed to evaluate the crystallization temperature, melting temperature, and glass transition temperature and hence study the thermal properties. Fourier transform infrared spectrum was recorded to examine the functional groups in the glass and study the structural characteristics of the glass. It showed the presence of symmetrical and asymmetrical stretching vibration modes of P–O–P linkages, bending modes of P–O in PO4, bending and stretching vibrations of OH groups and P–O–H water absorbance in the glasses. The absorption spectra of the prepared glasses in the UV–visible region (wavelength 200–1100 nm) were taken to study the optical properties of the glasses. The urbach energy and optical energy bandgap values are determined using Davis–Mott method. The refractive index of all the prepared glass samples is also measured and these values are used to determine the corresponding molar refraction, the molecular polarizability of oxide ions, dielectric constant, reflection loss, metallization criterion, electronic polarizability of the oxide ions, interaction parameter, electronegativity, optical basicity, and electric susceptibility of all the glass samples using appropriate formulae.

Photon and neutron shielding performance of boron phosphate glasses for diagnostic radiology facilities

Abstract This study focuses on radiation shielding characteristics of Li2O, Al2O3 and ZnO-doped boron phosphate glasses containing PbO and Bi2O3. Mass attenuation coefficient (μ/ρ) values of the glasses have been calculated using MCNPX code at various photon energies ranging from 60 to 120 keV and compared to those of XCOM software. The obtained results exhibited that MCNPX and XCOM are in good agreement at all energies. Some shielding parameters such as effective atomic number (Zeff), effective electron density (Nel), half value layer (HVL), mean free path (MFP) and Photon transmission factors (TF-photon) were determined using the obtained mass attenuation coefficients. Moreover, macroscopic effective removal cross sections (ΣR) and neutron transmission factors (TF-neutron) for fast neutrons have been evaluated. To simulate the attenuation properties of investigated glasses in a diagnostic radiology operation facility (control room), each boron phosphate glass sample was placed in front of a mathematical human head phantom namely SNYDER. For the glasses under examination, average photon flux in the eight detection points, which were located in different points of SNYDER head phantom, was calculated. Among the studied glasses, BPM4 sample has showed superior photon and neutron radiation shielding effectiveness. It can be concluded that boron-doped glasses are superior shielding materials for both gamma ray and neutrons.

Physical, optical and morphological studies of V2O5 doped zinc lead lithium phosphate (ZnPbLiP) glasses

Abstract Vanadium ion doped zinc lead lithium phosphate glass samples are prepared by melt quench method. X-ray diffraction studies confirmed the amorphous nature of all the prepared glasses. The density and refractive index values of these glasses are evaluated using the Archimedes method and Abbe’s refractometer respectively. The values of density found to be in between 3.6363 and 3.6666 g/cm3. The refractive index values are observed in the range 1.5605–1.5620. An increasing trend has been observed in density and refractive index from the simultaneous variation of Li2CO3 and V2O5 in the host matrix. Optical absorption spectra of these samples exhibited two absorption bands at 548 and 738 nm which indicate the characteristic absorption peaks of V4+ ions. The optical basicity values of the studied glasses V1–V5 are identified to slightly vary from 0.6736 to 0.6718, which represents electron donor ability of oxide ions to the cations. The knowledge on optical basicity finds immediate applications in the design of the novel optical functional materials like polarizers, detectors and modulators with higher optical performance. The morphological variations have been observed in the studied glasses upon doping of V2O5 by using Scanning Electron Microscopy.

Concentration dependence of visible luminescence from Pr3+-doped phosphate glasses.

To clarify the concentration dependence of visible fluorescence of Pr3+, a series of phosphate glass samples with Pr3+ concentration from 0.05 to 3.0 mol% were fabricated. Steady and dynamic spectroscopic characteristics of Pr3+-doped phosphate glasses were systematically investigated. When the Pr3+ concentration was small, only one visible fluorescence band can be observed at 596 nm, which was ascribed to the transition of 1D2 → 3H4. With increasing Pr3+ concentration from 0.05 to 0.5 mol%, since the multi-phonon relaxation rate of 3P0 was largely quicker than that of 1D2. Increasing Pr3+ concentration from 0.5 to 3 mol%, increasing two other fluorescence bands at 612 nm and 640 nm, which were assigned to the transitions of 3P0 → 3H6 and 3P0 → 3F2, respectively. It was due to the cross relaxation probability between [1D2: 1G4] and [3H4: 3F4] increased, which results in quicker decay rate of 1D2. The fluorescence lifetime of 1D2 decreased from 173 to 6 μs with increasing Pr3+ concentration from 0.1 to 3 mol%, which due to the cross relaxation probability between [1D2: 1G4] and [3H4: 3F4] increased, resulting in quicker decay rate of 1D2. Fitting the concentration dependence of fluorescence lifetime demonstrated that the cross relaxation arising from dipole-dipole interactions between Pr3+ ions.