Sodium Borate Glasses Research Articles

Effect of CuO addition on the structural, electrical and dielectric properties of the sodium borate glasses

The sodium borate glasses doped with different CuO content (70B2O3˗30Na2O˗xCuO with x = 0, 2, 4, 6 and 8 mol%) have been prepared using the conventional melt-quenching technique. The amorphous nature of the prepared samples has been identified by X-ray diffraction (XRD). The experimental and theoretical density, the molar volume, and the oxygen packing density have been defined. The effect of CuO incorporation into the 70B2O3˗30Na2O glass base on the electrical and dielectric properties has been studied. The D.C. electrical parameters have been measured in the temperature range 323˗483 K, while the dielectric parameters have been measured in the temperature range 333˗483 K and the frequency range 10−1˗ 107 Hz. The D.C. electrical conductivity increases while the activation energy decreases by increasing CuO content (mol%). The conduction type is ionic which CuO inserts into the glass structure as a glass modifier. The A.C. study reveals that all investigated glasses obey the correlated barrier hopping model (CBH). Moreover, the dissipation factor peaks indicate the glasses' relaxation nature which has been further analyzed from the real and imaginary parts of the electric modulus.

Characterization of the anomaly in immediate aqueous interactions of sodium borate glasses by dynamic vapour sorption with in-situ Raman

This study applied a novel technique; dynamic vapour sorption (DVS) with in-situ Raman spectroscopy, as well as complementary techniques of attenuated total reflectance-Fourier transform infrared spectroscopy and X-ray diffraction, to investigate the effect of sodium content on the immediate aqueous reactivity and reactions of a range of melt-quench-derived binary sodium borate glasses (SBGs): xNa2O-(100-x)B2O3 (x = 18, 23, 30 and 35 mol%). DVS gravimetrically measured the effect of controlled relative humidity (RH) values on SBGs, while in-situ Raman monitored their structural changes in real time. It was found that the glass boron coordination, glass transition temperature, as well as weight change and percentage of crystallinity post exposure to vapour, along with threshold % RH to initiate sorption, and threshold time to initiate crystallization under 90% RH demonstrated the anomalous variation with increasing sodium content in glasses. Relative to other formulations, 30Na2O–70B2O3 showed the lowest weight change and crystallinity after vapour desorption, and highest threshold % RH and longest threshold time. There was also a correlation between vapour- and water-induced reactions, as determined by reaction rates and structural changes. Specifically, lower glass network connectivity or non-bridging oxygen formation fostered their crystallization when exposed to either vapour or water, leading to higher weight change in aqueous environments. In sum, the results of this study validated the coupling of DVS with in-situ Raman spectroscopy in characterizing the reactivity and mechanisms of aqueous interactions of SBGs.

Novel methodology to determine thermal properties of nanoparticles exclusively based on SAXS measurements applied to Bi nanocrystals and nanodroplets in a glass matrix

A novel methodology is presented to determine thermal properties of polydisperse nanocrystals and/or nanodroplets embedded in a homogeneous matrix using small-angle X-ray scattering (SAXS). It is based solely on SAXS measurements at multiple temperatures and multiple moduli of the scattering vector. The proposed methodology can quantify the linear coefficients of thermal expansion of confined spherical nanocrystals and/or nanodroplets and the radius dependence of the melting temperature of confined spherical nanocrystals, even in samples with a broad size distribution. It is described through its application on a nanocomposite consisting of Bi nanocrystals/nanodroplets embedded in a sodium borate glass matrix. The linear coefficient of thermal expansion of Bi nanocrystals in the glass was ca 50% higher than that of bulk crystalline Bi, and the coefficient of liquid Bi nanodroplets was 25% smaller than that of bulk liquid Bi. The melting temperature of the spherical Bi nanocrystals decreased by ca 130 K when particle radii decreased from 82 to 23 Å. Even though SAXS measurements are generally expected to provide low-resolution structural parameters, this demonstrates that this technique allows for the characterization of rather weak temperature-dependent variations of size parameters during in situ heating processes and across melting transitions.

Composition dependence of transparency, optical, ligand field and radiation shielding properties in CdO–Fe2O3–Na2O–B2O3 glasses

Glasses are promising and efficient radiation shielding materials. However, they still suffer from low transparency with different types of additions, which need improvements for better transparency, consistency, and service life. This paper shows the significant improvements in radiation shielding and optical properties of cadmium oxide (CdO) and iron oxide (Fe2O3) sodium borate glass system upon changing CdO/B2O3 ratios. Optical absorbance and transmittance were measured, while the band gap values were obtained from investigating the fundamental absorption edges using Tauc's plot. Our analyses show that all glass samples show good transparency in the visible range; but the transparency slightly decreases with increasing CdO/B2O3 contents. Moreover, with increasing CdO/B2O3 contents, the BO4 units increase, the density increases, and the BO3 units decrease. Furthermore, with increasing CdO/B2O3 contents, the fundamental absorption edges shift toward higher wavelengths, and the optical band gaps decrease. Also, with increasing CdO/B2O3 contents, the linear and nonlinear refractive indices increase. These behaviors were justified by electronegativity decreases and electronic polarizability increases. On the other hand, the radiation shielding properties, like the mass attenuation coefficient and half-value layer, show enhanced behaviors with further CdO additions. The combination of enhanced radiation shielding properties and enhanced transparency makes the present glasses good candidates in the radiation shielding field.

Nonlinear optical properties of gold nanoparticles containing borate glasses at spectral region of surface plasmon resonance

Herein, we subjected the sodium borate glass activated with gold nanoparticles (NPs) to thermal treatment at 500 °C for different holding time to improve their nonlinear optical (NLO) characteristics in visible spectral region. The linear optical density and microscopic measurements confirmed the presence gold NPs in the glass. The outcomes also divulged the growth of Au NPs with an annealing schedule. The NLO attributes were ascertained through the Z–scan method, in which the samples were pumped at 532 nm utilizing nanosecond laser pulses fired at a rate of 1 kHz. Open aperture Z–scan measurements disclosed the existence of two–photon absorption nonlinearity, whereas closed aperture Z–scan experiments revealed the presence of self–defocusing nonlinear refraction in the studied glasses. The measurements unveiled the enhance trend of two–photon absorption and nonlinear refraction coefficients of glass host with thermal holding time owing to the growth of NPs. It was identified that the titled glass embedded with gold NPs annealed for 7 h at 500 °C owes maximum NLO features. Therefore, NBAu–7 glass examined in the current sturdy is beneficial for bio–imaging, optical limiting and NLO nanophotonic applications.

Gold nanoparticles enhanced femtosecond nonlinear optical properties of sodium borate oxide glasses

We present results from our experimental measurements on the effect of annealing and intensity–dependent femtosecond (MHz) third–order nonlinear optical (NLO) attributes of gold nanoparticles (NPs) embedded sodium borate glass specimens. A melt–quench procedure was used to fabricate the gold nanoparticle–loaded sodium antimony containing borate glasses, which were then subjected to different schedules of thermal treatment at 500 °C. The highest saturation intensity and nonlinear refraction magnitude were observed for the 7–hour annealed glass specimen (i.e., for NBAu–7 glass). Thus, on the NBAu–7 glass, intensity–sensitive NLO measurements were performed. The saturable absorption behavior that was detected at lower peak intensities switched to reverse saturable absorption during the exposure of NBAu–7 glass with high fluence laser pulses. While the sign of the nonlinear refraction remained unchanged, the magnitude increased. The methodology examined in this work may enable the fabrication of borate–based glasses loaded with gold NPs with high saturation intensities and robust nonlinear refractive index magnitudes to be used in optical switching operations. The results of the current study support that the NBAu–7 glass is advantageous for optical switching functions when exposed to low–energy laser pulses. In contrast, the same glass benefits optical limiting functions when exposed to high–fluence laser pulses.

Effect of BaO doping on the structural and optical properties of some cerium-copper sodium borate glasses

Effect of BaO doping on the structural and optical properties of some cerium-copper sodium borate glasses

Influence of Rare Earth Ions (REIs) on the Visible Emission of Magnesium Sodium Borate Glasses

Borate glass systems have been extensively studied for practical applications in optical display devices by virtue of their peculiar luminescence efficiency. However, the attainment of high emission from borate glass materials via apposite control of rare earth ions (REIs) contents remains a topical issue in Material Physics. In this paper, we report the influence of REIs (Dy3+, Eu3+, and Sm3+) on multiple-colour emission of magnesium sodium borate (MSB) glasses fabricated by using the conventional melt-quenching method. These glasses were optically characterized via X-ray Diffraction (XRD), UV-VIS-NIR and Photoluminescence techniques. The XRD pattern confirms the amorphous nature of the as-prepared glasses. The absorption spectra disclosed several absorption bands at 347 nm (6H15/2 → 6P7/2) for Dy3+, 393 nm (7F0 →5L6) for Eu3+ and 403 nm (6H5/2 →6P5/2) assigned for Sm3+ respectively. Also, the emission spectra radiate at 463 nm (4F9/2 → 6F11/2 + 6H9/2), 612 nm (5D0 → 7FJ) and 599 nm (4G5/2 → 6H7/2) for Dy3+, Eu3+, and Sm3+ correspondingly, wherein Dy3+ emits blue, yellow, and red light, Eu3+ emits red light and Sm3+ emits reddish-orange light. Finally, 1.0 mol% content of Dy3+, Eu3+, and Sm3+ in MSB glasses was found to be optimal and hence considered the best optical host for colour display devices.

Structural and spectroscopic properties of V2O5 doped zinc bismuth sodium borate glasses

Zinc bismuth sodium borate glasses with chemical composition (50-x)Bi2O3-30B2O3-(x-0.5)ZnO-20Na2CO3-(0.5)V2O5 [where x = 10, 15, 20, 25] were prepared by melt quenching technique. The prepared samples were studied by means of XRD, EPR, optical absorption and FTIR techniques. The amorphous nature was confirmed by the X-ray diffraction studies. The spin-Hamiltonian parameters (g & A) values, number of spins and paramagnetic susceptibility values have been calculated. The spin-Hamiltonian parameters indicate that the present glass samples are in octahedral sites with tetragonal distortion. The optical absorption spectra of VO2+ ions in the present glass system show single absorption band at ≈ 628 nm. The optical bandgap energies (Eopt) and Urbach energies (ΔE) have been calculated from the ultraviolet edges. The FTIR spectra reveal the BO, BO3, ZO, and BO4 bands in the present glass system.

Enhanced Er3+ photoluminescence in sodium borate glasses containing silver nanoparticles for photonic functionalities

Herein, the titled glass routed with silver nanoparticles (achieved using thermal–reducing agent) containing trivalent erbium ions was synthesized via the melt–quench process. The electronic microscopic and linear absorption outcomes of glasses confirmed the formation of Ag0 nanoparticles. The prepared glass specimen was annealed at 400, 450 and 500 °C, it was identified that the photoluminescence properties were highest at 450 °C. Therefore, we considered this 450 °C as optimized temperature, since further annealing at this temperature for different durations causes significant improvement in photoluminescence properties compared to the properties obtained at other temperatures. The annealing at 450 °C for was performed for 0, 5, 10, 15 and 25 h to understand the influence of annealing duration on the optical absorption, visible and infrared photoluminescence properties of the prepared glass system. The photoluminescence intensity and related parameters such as bandwidth, gain bandwidth and quantum efficiency and also lifetime values of excited state for infrared emission transition were improved monotonously with annealing duration. The augmentation in the investigated properties was ascribed to the local field–produced by silver nanoparticles and the energy transfer from silver nanoparticles to erbium ions. The outcomes instantiate that the titled glass embedded with silver nanoparticles containing erbium ions annealed for 15 h at 450 °C could be useful for optoelectronic and photonic applications.

Silver nanoparticles improved infrared photoluminescence of Nd3+ doped sodium borate glasses

Method of melting and quenching was used to prepare the alkali borate–based glasses embedded with Nd3+ ions and silver nanoparticles (Ag NPs). In the as–prepared glass, silver NPs were formed by loading the thermal reducing agent such as antimony trioxide in the composition. The optical absorption and microscopic outcomes confirmed the growth of silver NPs in the prepared glass system. The prepared glass was annealed at 450 °C for 0, 5, 10, 15, and 25 hrs to tune the spectroscopic and photoluminescence features of Nd3+ ions loaded in the glass. The photoluminescence intensity and related features were enhanced continuously with heat treatment schedule. However, subsequently the features were reduced at longer schedule. The variation of these features was ascribed to the local field–generated silver NPs. The results revealed that the entitled glass could be utilized for photonic and optoelectronic applications when activated with Nd3+ ions and routed with Ag NPs.

Characterization of sodium and calcium addition on immediate aqueous interactions of binary borate glasses by dynamic vapour sorption with in-situ Raman

This study describes a novel technique; dynamic vapour sorption (DVS) with in-situ Raman spectroscopy, to investigate the reactivity and mechanisms of aqueous interactions of bioactive borate glasses (BGs). Two melt-derived binary-BGs; (70)B2O3-(30)Na2O and (70)B2O3-(30)CaO (mol%), were investigated to compare the effect of sodium and calcium addition on boron coordination and aqueous interactions, via DVS and dissolution in deionized water. DVS, which gravimetrically measures the effect of exposing BGs to a controlled relative humidity, was applied to quantitatively evaluate their glass-water reactivity. Meanwhile, in-situ Raman monitored structural changes in real-time to demonstrate their different aqueous reactions and characterize vapour- and water-induced crystallization of sodium-borate glasses. In conclusion, correlation of structural changes and reaction rates between vapour- and water-induced reactions validated the coupling of DVS and in-situ Raman as a more sensitive approach to characterize aqueous reactivity and reactions of BGs compared to traditional methods, such as submersion in aqueous solutions.

Structural and optical absorption coefficient analysis of barium lead sodium-borate glass doped with graphene nanopowder

In this study, some barium-lead sodium borate graphene-doped glasses have been prepared. The preparation is based on the concept of weight percentage using the fast quenching methodology. The internal phases of the as-prepared solid samples have been characterized using X-ray diffraction (XRD), and Fourier Transform Infrared (FTIR). All characterization processes revealed the amorphous nature of the as-prepared samples, with an increase in the crystallinity degree as the graphene content increased. On the other hand, the optical characterization was achieved using UV–vis, which revealed a decrease in both direct and indirect optical band gaps from 3.5 to 3.32 eV and from 2.95 to 2.66 eV, respectively, as the graphene content increased. The value of Urbach's energy decreased from 0.658 to 0.641 eV, which is an anomalous behavior because it is the same as that of the optical band gaps. At the same time, the decrease in the value of Urbach’s energy confirmed the results of (XRD) about the crystallinity degree. The absorption coefficient spectra have been simulated using the hydrogenic excitonic model (HEM), where some useful parameters were obtained. Such parameters indicate the indirect optical transition as the dominant absorption mechanism, which is a common feature of amorphous solids. The obtained data suggested that graphene nanopowders as a modifier can be used to improve the effectiveness of oxide glasses for UV-blockers, radiation shielding, and greenhouse applications.

Changes in the structural and optical properties due to the incorporation of ZnO into cerium−cupric sodium borate glasses

Changes in the structural and optical properties due to the incorporation of ZnO into cerium−cupric sodium borate glasses

Alkali and alkaline earth zinc and lead borate glasses: Sintering and crystallization

Glasses in the systems Me 2 O-ZnO-B 2 O 3 with Me = Li, Na, K, Rb (MeZB), Na 2 O-ZnO-CuO-B 2 O 3 (NZCuB), CaO-ZnO-B 2 O 3 (CaZB), and Li 2 O-PbO-B 2 O 3 (LPbB) as a reference, were studied by differential thermal analysis, dilatometry, rotational viscometry, and heating microscopy. A decrease of viscosity and sintering range was found with decreasing number of fourfold coordinated boron. The viscosity of the alkali zinc borate glasses varies only slightly. LPbB and CaZB stand out by their reduced and increased viscosities, respectively. Sodium, potassium, and calcium zinc borate glasses possess a fragility above 76. All glasses were sintered to full density before crystallization. Mostly binary zinc borate phases govern crystallization. A ternary crystalline phase was detected only in the potassium containing sample. The Weinberg glass stability parameter ranges between 0.07 and 0.12. This is caused by the presence of several crystalline phases and varying melting points of even the same crystalline phase in different glass matrices. • Viscosity, fragility, and sintering do not significantly vary for different alkali ions. • All glasses sinter to full density before being crystallized. • Crystallization is governed by binary zinc borates in Li- and Na-containing glasses. • K 2 O⋅2ZnO⋅3B 2 O 3 crystallized in the potassium zinc borate glass.

Alkali and alkaline earth zinc and lead borate glasses: Structure and properties

Low melting Li 2 O-PbO-B 2 O 3 , Me 2 O-ZnO-B 2 O 3 , Me = Li, Na, K, Rb and CaO-ZnO-B 2 O 3 glasses were studied with Raman and infrared spectroscopies to advance the structural understanding of zinc borate glasses as potential candidates for substitution of lead containing glasses. Although the effect of type of alkali ions on the number (N 4 ) of fourfold coordinated boron (B 4 ) in the glasses is small, the alkali ions direct the type of borate groups, i.e., pentaborate in lithium, sodium, and calcium zinc borate glasses, as well as diborate in potassium and rubidium containing ones. Both groups were simultaneously found in Li 2 O-PbO-B 2 O 3 . Alkali ions are mainly responsible for the formation of B 4 -units and metaborate. Zinc ions favorably compensate non-bridging oxygen and partially form ZnO 4 . With decreasing N 4 and field strength of the alkali ions the atomic packing density, glass transition temperature and Young's Modulus also decrease. The coefficient of thermal expansion increases with decreasing N 4 . • In alkali-zinc-borate glasses alkali ions mainly neutralize the charge of B 4 -units. • Zinc ions favorably compensate the charge of non-bridging oxygens in the glasses. • The number of tetrahedral boron depends on the nature of the network-modifier. • The type of alkali ion and Zn or Pb ion directs the formation of borate units. • Alkali-glasses reflect a decrease of Young's Modulus with atomic packing density.

Structural and gamma ray shielding behavior of dual heavy metal oxide doped magnesium sodium borate glasses

The dual heavy metal oxide doped magnesium sodium borate glasses were fabricated using the melt quenching method. Bismuth concentration increases the density of current samples from 3.833 to 4.283 gcm−3. The amorphous nature is confirmed by the X-ray diffraction (XRD) pattern, which shows no obvious peak. This information is provided by Fourier transform infrared spectra (FTIR) peaks and bands, which may be used to identify samples' bending and stretching vibrations. Using EpiXS software, the radiation shielding parameters of four samples were determined for energies of 444, 678, 689, 779, 867, 964, 1005, and 1086 keV. The results demonstrated that when a portion of B2O3 is replaced with Bi2O3, the sample's radiation shielding efficacy improves. The TVL results showed that 8.37 cm of sample A4 can reduce the intensity of 1086 keV by 90 %, whereas 9.52 cm of sample A1 is required to reduce the intensity by the same amount. Sample A4, which has the most Bi2O3, has the lowest TVL, making it the best radiation shield.

Structural, optical, and radiation shielding features of newly developed BaZrO3/Na2O–B2O3 glass

In this work, the radiation shielding capacity of novel BaZrO3 perovskite-doped sodium borate glasses with compositions of 40Na2O–60B2O3+ x BaZrO3 (where x = 0, 10, 20, and 30% wt.) was examined. XRD and FTIR have been used to analyze the structural characteristics of the produced glass systems. The relative concentration of BO4 units in the sodium borate glass N4 decreased by adding 10% from BaZrO3 and then increased. Also, the optical energy increases from 3.2 eV to 3.34 eV as the BaZrO3 content reaches 10% and then drops to 3.15 eV with an increase in the BaZrO3 content to 30%. Further, glasses' electronic polarizability, reflection loss, and optical transmission were investigated. The gamma-radiation shielding characteristics of novel BaZrO3-based glasses were experimentally investigated. The MAC values enhanced from 0.0534 cm2/g for NB glass to 0.0685 cm2/g for NB+30% BaZrO3 at the energy of 1.333 MeV. Furthermore, the experimental and theoretical findings for mass attenuation coefficient (MAC) have also been compared utilizing Phy-X/PSD software. In addition, the exposure build-up factor (EBF), removal cross-sections of fast neutrons, and equivalent atomic numbers (Zeq) have been computed. According to the results, adding BaZrO3 perovskite seems to boost the gamma-ray shielding effectiveness of sodium borate glass.

Gamma photon and charged particle shielding features of praseodymium based glass matrix

Radiation shielding features of TePr glass system for helpful gamma-rays have been computed through FLUKA Monte Carlo code and Phy-X/PSD database. Linear attenuation coefficients (LAC) obtained with Phy-X/PSD and FLUKA code are found to be in good harmony with utmost relative difference < 3.7%. Based upon various parameters investigated, TePr1.2 (with highest amount of praseodymium) is found to be best shielding glass composition among the samples fabricated in this study for gamma-rays as well as charged particle beam of protons. The half value layer for the five glass samples between 0.284 and 2.51 MeV was estimated and we found that the HVL increases in the order TePr1.2, TePr1, TePr0.5, TePr0.2, TePr0. The proposed new glass system is found to have better shielding ability than commercial glasses and bismuth sodium borate glasses. The mass stopping power (MSP) for the tested glasses was reported, and we observed that MSP values for all the TePr glasses are not differing significantly. For protons, the SRIM based MSP values for TePr1.2 rise swiftly from 0.0612 to 0.135 MeV cm2/mg for kinetic energy range 0.01–0.14 MeV then decline slowly upto 0.0183 MeV cm2/ mg at 10 MeV.

Effect of Y3+ on the structural and photoluminescence properties of yttrium-doped sodium borate glass.

Glass of the composition 70%B2 O3 -(30-x)%Na2 O-x%Y2 O3 with x = 0, 0.5, 1, 1.5, 2, and 2.5 mol% was manufactured using the melt quenching method. X-ray diffraction tests indicated the amorphous structure of the glass, with the presence of some YBO3 clusters in the high yttrium content samples. Fourier transform infrared spectra analysis proved the presence of different borate groups and linkages, in addition to nonsystematic changes in the ratio BO3 /BO4 in the glass. The forming ability of the glass was found to be approximately stable for the low Y3+ content samples and increased for the heavily doped samples. The density of the samples was found to increase as the Y3+ concentration was increased, whereas the molar volume decreased. The bond strength of the examined glass suggested that a covalent nature was dominant between bonds. All the Y3+ -doped glass was found to emit greenish-cyan light when excited at . Photoluminescence intensity was shown to be enhanced by the generated YBO3 groups. The obtained correlated colour temperature values with 82.5% purity recommend the suitability of the glass for applications in outdoor illumination.