Sodium Borophosphate Research Articles

Impact of CdO on optical, physical, and radiation resistance of sodium borophosphate glasses

This article focuses on exploring the effects of CdO on the optical, radiation, and physical characteristics of sodium borophosphate glass with different compositions. The glass compositions included B2O3, Na2O, P2O5, and varying content of CdO from 0 to 12 mol %. One of the observed effects of adding CdO to the glass composition is a substantial increase in glass density. The density increased from 3.42 g/cm³ to 4.87 g/cm³ as the CdO increased. UV–visible spectroscopy was utilized to determine the optical bandgap and other correlated physical parameters. Bandgap values increased from 2.39 to 2.74 eV for Eoptind and from 2.51 to 2.82 eV for Eoptdi. Connections between the optical and physical characteristics of CdNaBP glasses are discussed. Moreover, different shielding parameters were assessed using Phy-X simulation software. This study explores the importance of radiation shielding efficiency and the positive impact of higher CdO content on photon blocking in sodium borophosphate glasses. The addition of CdO enhances the radiation shielding capabilities of this glass. Additionally, the study explored the gamma shielding properties. Hence, all these observations infer that the CdNaBP-12 glass sample is the most suitable for transparent radiation shielding applications.

Reassessment of Electrical and Dielectric Properties in the Borophosphate Glass System: A Promising Solid Electrolyte for High-Temperature Batteries.

This study investigates the conduction mechanism of ternary sodium borophosphate glass 30Na2O-(70 - x)B2O3-xP2O5 with 0 ≤ x ≤ 35 mol % from a different perspective, focusing on previously unreported high-temperature electrical and dielectric properties for potential solid electrolytes in high-temperature batteries. The glass composition with B2O3/P2O5 = 1 exhibits a conductivity of approximately 10-4 S/cm at 250 °C. Dielectric analysis supports this improved conduction, showing higher dielectric values and minimal energy dissipation during storage, indicating promising conductivity and favorable dielectric properties. This enhancement is attributed to the large-polaron (QMT) model, deduced from the power law exponent, due to the creation and spreading of lattice distortion of a long-range order with interconnected B4-O-P1 and B4-O-P2 linkages. Contrary to previous results, the glass transition temperature does not vary coherently with the conductivity and activation energy, displaying a discontinuity at 14 mol %. This discontinuity is caused by the initial extreme depolymerization of P2O5, leading to an increase in nonbridging oxygens (NBOs) within the glass network and forming B4-O-P0 linkages. Despite this, the ionic mobility of Na+ is continuously enhanced, correlated with the increase in the molar volume. This new perspective highlights the significant impact of both free volume expansion and reduced Coulombic effects on conduction improvement.

Functionalization of Phosphate and Tellurite Glasses and Spherical Whispering Gallery Mode Microresonators.

Active whispering gallery mode resonators made as spherical microspheres doped with quantum dots or rare earth ions achieve high quality factors and are excellent candidates for biosensors capable of detecting biomolecules at low concentrations. However, to produce quantum dot-doped microspheres, new low melting temperature glasses are sought, which require surface functionalization and antibody immobilization for biosensor development. Here, we demonstrate the successful functionalization of three low melting point glasses and microspheres made of them. The glasses were made from sodium borophosphate, sodium aluminophosphate, and tellurite, and then, they were functionalized using (3-glycidyloxypropyl)trimethoxysilane in ethanol- and toluene-based protocols. Proper silanization was confirmed by energy-dispersive X-ray spectroscopy and fluorescence microscopy of an amino-modified luminescent oligonucleotide probe. Fluorescence imaging showed successful silanization for all tested samples and no degradation for aluminophosphate and tellurite glasses. The strongest signal was registered for tellurite glass samples functionalized using the toluene-based silanization protocol. This conclusion implies that this functionalization method is the most efficient and is highly recommended for future antibody immobilization and biosensing application.

Synthesis, bright red-emitting and low thermal quenching behavior of europium(Ⅲ)-activated sodium borophosphate phosphor

In this work, trivalent europium (Eu3+) activators were incorporated into sodium borophosphate Na3B6PO13 via replacing Na+ ions. The large band gap is verified via the experimental diffuse reflectance data and theoretical calculations. The concentration quenching with the optimal 13 % Eu3+activators is caused by quadrupole–quadrupole interaction. A vibrant red-emitting behavior is illustrated when excited at 394 nm. For Na3B6PO13:13 %Eu3+, the low thermal quenching behavior (86 %@423 K) and good chromaticity stability (0.0073@473 K) is revealed. Finally, we utilize the red-emitting material to construct a white light-emitting diodes, producing the low correlated color temperature (4250 K) and satisfactory color rendering index (82). The title material exhibits promise for illumination application.

Structural and gamma-ray attenuation of mixed former lead-free borophosphate glasses

Sodium borophosphate parent glass in conjugation with other derived samples containing adaptable amounts of bismuth oxide at the expense of phosphate partner was prepared via the ordinary melt-quenching technique. Synthesized samples were investigated using Fourier transforms infrared (FTIR) spectroscopy. The undercover or overlapped peaks were estimated using the deconvolution analysis technique (DAT). The collected IR spectra refer to the presence of combined PO4 and BO3+BO4 groups besides the presence of Bi–O vibrations upon the addition of Bi2O3. The assignments of the IR peaks are facilitated by the conduction of deconvolution processes. The density of the studied glass was estimated and some selected physical parameters including molar volume and packing density were calculated.Gamma-ray shielding competence of studied borophosphate glasses has been explored through user online friendly software (Phy-X/PSD) in combination with their abilities to act as shielding candidates as a function of Bi2O3 content. In addition, linear and mass attenuation coefficients (μm) combined with other physics parameters were calculated to assess the proper action of bismuth oxide in the shielding mechanism. Sample NABP10Bi enriched with Bi2O3 possessed the highest values of LAC, MAC, and Zeff. The HVL parameter followed the trend that was considered to be dependent on the bismuth oxide concentration.

Structure-Property Correlation in Sodium Borophosphate Glasses Modified with Niobium Oxide

Bulk glasses of the series (100−x)[0.4Na2O-0.2Nb2O5-0.4P2O5]-xB2O3 with x = 0–48 mol% B2O3 were prepared by slow cooling in air. Their glass transition temperature increases within the range of 0–16 mol% B2O3, but further additions of B2O3 result in its decrease. Their structure was investigated by Raman, 11B, and 31P MAS NMR spectroscopy. The relative number of BO4 units decreases with increasing B2O3 content, while the number of BO3 units increases up to 59 % at x = 48. The upfield shift of a broad resonance peak in the 31P MAS NMR spectra is ascribed to an increasing connectedness of the structural network with increasing B2O3 content. Strong Raman band at 916–929 cm−1 shows on the presence of NbO6 octahedra in the structural network of these glasses. With the B2O3 addition, a decrease in DC conductivity is observed, which is attributed to the decrease in the concentration of Na+ ions.

Impact of copper oxide on the structural, optical, and dielectric properties of sodium borophosphate glass

Sodium borophosphate glasses containing copper oxide (CuO) have produced by melt annealing technique. Phosphate units are presented in Q2, whereas the borate groups are presented as trigonal and tetraborate units. The addition of CuO in the network former modifies the characteristic mid region of infrared bands or peaks. The base glass sample has a density of 2.57 g/cm3 raising to 2.71 g/cm3 after doping with 0.1 CuO. The absorption edges of such glass shifted towards lower photon energy due to the formation of non-bridging oxygens (NBOs). With the increase in the copper content from 0 to 0.1 mole fraction, the optical transition values decreased from 3.682 to 1.672 eV. The real and imaginary part of dielectric constants decreased as the applied frequency increase due to the dipolar, interfacial, and dielectric polarization effects. The relaxation process has observed at high frequency and 0.1 CuO sample correlated to the formation of NBOs.

Structural and some physical properties of Sodium Boro-phosphate Glass Containing Mill Scale.

Structural and some physical properties of Sodium Boro-phosphate Glass Containing Mill Scale.

Near-UV-excited photoluminescence of terbium (Ⅲ)-activated lithium sodium borophosphate phosphor

At present, borophosphate-based fluorescent powder with doped rare earth activators becomes a hot issue in lighting and display industry. Series of Tb3+-activated Li2NaBP2O8 (LNBP) products were constructed via a solid state reaction procedure. The absorption behavior, dopant Tb3+ concentration- and temperature-dependent photoluminescence, and colorimetric properties have been studied in depth. The photoluminescence optimization is as follows: Upon the excitation of near-UV light, the LNBP:Tb3+ product can produce strong visible light with a dominant peak at 544 nm because of the intrinsic 4f optical transitions of Tb3+, and tuning dopant Tb3+ concentration results in the variation of the emitting light color from white to yellowish-green to yellow-green. The LNBP:0.03Tb3+ phosphor possesses the maximal photoluminescence intensity. The finding indicates that the title product with good thermal stability is a promising phosphor for solid state light applications.

SrO-reinforced potassium sodium borophosphate bioactive glasses: Compositional, physical, spectral, structural properties and photon attenuation competence

The melt quenching process is assumed in making the glass system 45P2O5-15B2O3-22Na2O-(18-x) K2O: xSrO where x = 0-12 mol%, namely as S1-S5. Compositional, physical, spectral, structural properties and radiations attenuation competences of S1-S5 bioglasses have been investigated compared to ordinary concrete (OC) cortical bone (CB) and soft tissue (ST). The density of the prepared bioactive glasses has been found to increase with an increase in the SrO content, whereas an opposite trend has been observed in the molar volume. FTIR study shows the existence of different structural groups such as BO3, BO4 and BPO4 units in the network. Optical absorption spectra of the glasses revealed that the cutoff wavelength decreases with increased in SrO content. The maximum (minimum) MAC values were 7.986 (0.021), 7.925 (0.0214), 7.863 (0.0217), 7.865 (0.0217) and 8.837 (0.022) cm2/g for S1, S2, S3, S4, and S5, respectively. The maximum value of LAC was also obtained at 15 keV with values equal to: 18.528, 18.942, 19.343, 19.898, and 20.144 cm−1 respectively for S1-S5. At 0.1, 1.0, and 10 MeV, values of HVT of the glasses were 1.72, 1.54, 1.38, 1.34, and 1.14 cm for S1-S5, respectively, however, the HVT of S1–S5 were less than that of ordinary concrete (OC). The MFP was reduced as SrO content of the S1-S5 glasses increased. Results of the calculated radiation interaction parameters showed that S5 is a better photon, proton and electron absorber compared to the other four bioactive glasses in this study. Improving in photon absorption of the glasses was recorded for higher SrO content. The effect of SrO addition on photon (energy) absorption is more significant for photon energies less than 0.2 MeV. The studied bioactive glasses can function better than ordinary concrete for photon shielding applications.

Microstructured SHG patterns on Sm2O3-doped borophosphate niobium glasses by laser-induced thermal poling

A microstructured SHG pattern on Sm2O3-doped sodium borophosphate niobium (SmBPN) glasses was obtained by laser-induced thermal poling. The optical properties of SmBPN glasses were recorded by UV/Vis/NIR transmission spectra. In situ laser-induced heating of the SmBPN glasses without and with preheating was characterized by an infrared thermal camera. A laser-induced microstructured pattern was written on the ITO electrode, resulting in a local electric field enhancement during the poling process. Laser-induced heating together with the enhanced local electric field of the microstructured electrode governed the geometry and strength of the electrical field of these SmBPN glasses. This poling process could be a potential method to design second-order optical properties or even to fabricate microstructures.

The effect of the sodium content on the structure and the optical properties of thermally poled sodium and niobium borophosphate glasses

Six niobium rich glasses presenting different sodium contents were synthetized. On the basis of complementary infrared and Raman analysis, the influence of the sodium content and its role on the structure of the glasses prior to and following poling was examined. Correlative second harmonic generation (SHG)/Raman microscopy on the poled glasses cross section has shown a co-localization of the SHG signal and the structural variations. It also evidenced similar structural rearrangements whether sodium is removed through poling (230–300 °C) or through the alkali content defined by the starting glass compositions (melted at 1300–1500 °C). The effect of the sodium content on the optical properties, prior to and after thermal poling, is also discussed. It was found that refractive index variations induced by poling (ranging between 10−3 and 3 × 10−2) are mainly the result of a density decrease in the poled region rather than compositional and structural changes. The electro-optic origin of the poling-induced second order nonlinear response is confirmed by the Maker Fringe SHG analysis, and the evolution of χ(2) (2–2.5 pm/V) with the sodium content is discussed based on a selection of parameters influencing either the third order susceptibility [χ(3)] or the internal electric field strength of the poled layer.

Surface chemical analysis and white-emitting characterization of dysprosium-activated single-phase lithium sodium borophosphate

Doping trivalent dysprosium ion as an activator into inorganic matrix materials is an interesting strategy for exploring white emitting single-phase materials. In this study, a new borophosphate Li2NaBP2O8 (LNBP)-based phosphor activated with Dy3+ was developed via a solid phase reaction at 873 K for 48 h. The phase structure, surface information, Dy3+ content-dependent white photoluminescence, and content quenching mechanism were characterized. By tuning dopant Dy3+ content to 1 mol%, the color coordinates of emitting light for the product changed from the green to white region under 351 nm irradiation. The white emission of single-phase LNBP:1%Dy was composed of 4F9/2 → 6H15/2 (482 nm, blue) and 4F9/2 → 6H13/2 (573 nm, yellow) components. A dipole – dipole interaction mainly contributed to the content quenching phenomenon. Our findings suggest that single-phase borophosphate-based phosphor activated with Dy3+ is an available source for acquiring white emitting performance.

A Novel Sodium and Chromium Borophosphate Na{Cr[BP2O7(OH)3]}: Synthesis, Crystal Structure, Hydrogen Bonding, and Comparative Crystal Chemistry

A novel sodium and chromium borophosphate, obtained by hydrothermal synthesis in the Na2O–P2O5–B2O3–Cr2O3–Н2О system, has been investigated using X-ray diffraction and IR spectroscopy. The monoclinic cell parameters are found to be a = 10.4220(3) A, b = 8.2468(2) A, c = 9.2053(3) A, β = 116.568(4)°, and V = 707.63(4) A3; sp. gr. С2/с. The structure is interpreted and refined to the final reliability factor R1 = 2.23% in the anisotropic approximation of atomic displacements using 1311 reflections, I > 2σ(I). The novel compound is relative to the family of alkaline borophosphates with the general formula A{M[BP2O7(OH)3]} (A is an alkaline or alkaline-earth element; M is a transition метал) and is described by the crystallochemical formula (Z = 4) Na{Cr[BP2O7(OH)3]}, where the compositions of borophosphate anion and microporous framework are in square brackets and braces, respectively. The presence of alternative systems of strong symmetric hydrogen bonds is established; the localization of all hydrogen atomic sites has made it possible to analyze them in detail. An additional electron density peak is found, which can be interpreted as a statistically distributed proton H+. The IR spectrum is characteristic of compounds with strong hydrogen bonding; it confirms the statistical proton distribution over subsites around the inversion center. It is suggested that representatives of this family may possess proton conductivity.

Effect of Na2SO4 substitution for Na2O on the structural and electrical properties of a sodium borophosphate glass

The effects of Na2SO4 substitution to Na2O on the structural and electrical properties of a sodium borophosphate glass system prepared by the melt/quenching method were investigated by means of different techniques. The amorphous nature of the glass was evidenced by X-ray diffraction (XRD). Differential scanning calorimetry (DSC) has showed a decrease of glass transition temperature (Tg) while density measurements showed an increase of the molar volume Vm of the glass with the addition of Na2SO4. Raman and infrared (FTIR) spectroscopies have revealed a significant structural change which confirms the behavior of Tg and Vm of the glass. Impedance measurements showed that the overall electrical behavior originates from bulk contribution, whereas the frequency dependence of ac conductivity does not seem to follow the simple Jonscher's power law due to the electrode polarization effects. Moreover, the dc conductivity exhibits an Arrhenius-type behavior with temperature. The decrease of the activation energy and the increase of the electrical conductivity with the addition Na2SO4was discussed based on the results of the structural investigation of the glass.

The internal friction of lithium and sodium borophosphate glasses

Alkali borophosphate glasses have recently gained strong interest, not only for their fundamental importance due to the mixed glass former effect but also because of their potential applicability as solid state electrolytes in energy harvesting devices. In the present work, internal friction measurements of lithium and sodium borophosphate glasses have been performed in order to look for further insights on the relationships between the ionic conduction mechanism and the structure of the glasses that has been previously determined. Absorption of acoustic waves shows two marked internal friction peaks with activation energy in the range of the activation energy for the ionic conduction of the glasses between 0.5 and 0.7 eV. Furthermore, the substitution of phosphorus by boron network former results in the decrease of the activation energy associated to both processes in parallel to the Ea of the ionic conduction of alkali cations; and the relationship between the areas of both peaks suggests a change of the distribution of alkali ions between positions energetically different in agreement with the structural changes of the glass network.

Dielectric Study of Lithium and Sodium Borophosphate Glasses

Ionic conductivity and dielectric properties such as dielectric permittivity and loss tangent for the samples of lithium and sodium borophosphate glasses were investigated using the electrical conductivity measurements in the range of frequency from 10 Hz to 2 MHz and various temperatures below Tg. The measured data of ac conductivity were described according Jonscher's power law and experimental values of imaginary part of electric modulus were fitted by KWW function. From the fitted parameters, the activation energies for conduction and relaxation time were found which characterize the hopping processes and transport mechanism in these ion conducting glasses.

Positive and Negative Mixed Glass Former Effects in Sodium Borosilicate and Borophosphate Glasses Studied by (23)Na NMR.

Glasses with varying compositions of constituent network formers but constant mobile ion content can display minima or maxima in their ion transport which are known as the negative or the positive mixed glass former effect, MGFE, respectively. Various nuclear magnetic resonance (NMR) techniques are used to probe the ion hopping dynamics via the (23)Na nucleus on the microscopic level, and the results are compared with those from conductivity spectroscopy, which are more sensitive to the macroscopic charge carrier mobility. In this way, the current work examines two series of sodium borosilicate and sodium borophosphate glasses that display positive and negative MGFEs, respectively, in the composition dependence of their Na(+) ion conductivities at intermediate compositions of boron oxide substitution for silicon oxide and phosphorus oxide, respectively. A coherent theoretical analysis is performed for these glasses which jointly captures the results from measurements of spin relaxation and central-transition line shapes. On this basis and including new information from (11)B magic-angle spinning NMR regarding the speciation in the sodium borosilicate glasses, a comparison is carried out with predictions from theoretical approaches, notably from the network unit trap model. This comparison yields detailed insights into how a variation of the boron oxide content and thus of either the population of silicon or phosphorus containing network-forming units with different charge-trapping capabilities leads to nonlinear changes of the microscopic transport properties.

Charge Compensation in Sodium Borophosphate Glasses Studied by 11B{23Na} and 31P{23Na} Rotational Echo Double Resonance Spectroscopy

Network former–network modifier interactions in three sodium borophosphate glasses have been probed by 11B{23Na} and 31P{23Na} rotational echo double resonance (REDOR) experiments. For the compositions chosen essentially all of the boron atoms in these glasses are four-coordinated and, thus, of formally anionic character, whereas the majority of the phosphorus species are of the (nominally charge-neutral) P(3) type. Despite this fact, the dipolar second moments M2(11B{23Na}) and M2(31P{23Na}) extracted from these REDOR data indicate that the sodium cations interact significantly more strongly with the phosphate than with the borate species. As a matter of fact, the distance sums ∑rP–Na–6 calculated from these second moments are close to those measured in sodium ultraphosphate glasses with similar sodium concentrations, whereas the corresponding ∑rB–Na–6 values are significantly smaller than those measured in sodium borate glasses with comparable sodium concentrations. These results are corroborated by com...

Structural Origin of the Mixed Glass Former Effect in Sodium Borophosphate Glasses Investigated with Neutron Diffraction and Reverse Monte Carlo Modeling

The mixed glass former systems 0.35Na(2)O + 0.65[xB(2)O(3) + (1 - x)P2O5] and 0.5Na(2)O + 0.5[xB(2)O(3) + (1 - x)P2O5] with x = 0-1 were investigated with neutron diffraction (ND) together with reverse Monte Carlo (RMC) modeling of 0.35Na(2)O + 0.65[xB(2)O(3) + (1 - x)P2O5]. The results show that the structure of both systems is reflected by an intermediate-range ordering, with a characteristic x-dependent length scale of about 4-6 angstrom and which contracts slightly with the increase of the Na concentration. Results obtained from RMC modeling of the 0.35Na(2)O + 0.65[xB(2)O(3) + (1 - x)P2O5] system, using both previously reported X-ray diffraction (XRD) data as well as the here obtained ND data as independent constraints in the modeling, show that the intermediate-range structural features, notably the Na coordination and volume fraction of the conducting pathways, are only weakly dependent on the choice of the constraints used. In particular, we observe that the volume fraction of the conducting pathways and the activation energy for ionic conduction are only weakly correlated to each other, as opposed to what is found for binary alkali borate and phosphate glasses.