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The quencher concentration (cmax) of rare‐earth (RE3+) doped laser glass plays a pivotal role in achieving high laser gain. However, it is still challenging to quantitatively calculate and predict the cmax of RE3+ ions in laser glass. Here, we propose and demonstrate a robust method in predicting the local environment and the cmax of RE3+ in laser glasses from their neighboring glassy compounds (NGCs). Specifically, the NGCs method capably predicts the local environment of Er3+ ions in borate glasses (B2O3–BaO binary and B2O3–BaO–Li2O ternary glasses). Moreover, the NGCs' method accurately predicts the cmax of Er2O3 in borate glasses with an error of less than 5% compared to the experimental result, showing the promising prediction capability for the cmax of RE3+ ions. Based on the NGCs method, the cmax database of Er3+‐doped borate glasses is established for efficiently tailoring compositions with desired optical properties. This study offers a rapid and low‐cost route to design novel laser glasses. [ABSTRACT FROM AUTHOR]

Neutrons are widely used in national defense, security, and medical health fields. It is critical to realize neutron detection with high efficiency. The most popular neutron detection scintillators such as lithium glass and 6LiF/ZnS:Ag screen exhibit insurmountable limitations: the former usually has relatively rather low light yield and latter is opaque. In this research, we report the successful construction of the novel full inorganic composite scintillators by low temperature co‐firing technology. The composite scintillator is derived from the ZnS:Ag and borate glass matrix, and it shows better transparency compared with the standard 6LiF/ZnS:Ag screen. It exhibits excellent scintillation properties with the X‐ray induced emission intensity of these composite scintillators reaching approximately 2.46 times of the standard Bi4Ge3O12 (BGO) crystal. The light output under thermal neutron excitation can reach 75 000 photons/neutron. In addition, it presents excellent neutron detection performance with natural abundance of 10B isotope. Our research findings can serve as a valuable reference for the advancement of robust neutron detection materials, particularly in the domain of ZnS:Ag‐based full inorganic scintillator for neutron detection. [ABSTRACT FROM AUTHOR]

Distinctive luminescent properties and excellent stability of long persistent luminescent (LPL) glass‐ceramic hold promise for anti‐counterfeiting and encryption applications. However, rational synthesis and a deep understanding of the precipitation of dual‐phase microcrystals in glass substrate to improve the encryption level remain challenging. Here, we carefully designed the components based on the phase diagram and combined them with the glass‐forming region. By utilizing the different crystallization behaviors of SrAl2O4 and CaAl2O4 in the glass matrix to realize dual crystals coexistence in a borate glass matrix, which provides different crystal field environments for Eu2+ luminescence, thus obtaining excitation‐dependent tunable LPL characteristics in a single sample. Mechanism studies unveiled that this excitation‐dependent behavior arises from the differential capture of charge carriers by defect oxygen vacancies in the sample when charged with different laser sources, providing a channel for multimode anti‐counterfeiting encryption. This strategy of constructing a double crystal field in a glass matrix overcomes the stringent requirements of a single heat treatment method for the crystallization temperature of biphasic crystals, which could become a stable and promising advanced anti‐counterfeiting encryption material and provide new insights into the multi‐band luminescence regulation of rare earth ions. [ABSTRACT FROM AUTHOR]

The magneto‐optical properties of rare‐earth‐rich borate glasses prepared using a levitation technique were thoroughly investigated. Among the series of rare‐earth borate glasses, Tb2O3–B2O3 and Dy2O3–B2O3 glasses displayed remarkably large Faraday effects in the visible region. The Verdet constant of 58Tb2O3–42B2O3 reached −229 rad/T·m at 633 nm, surpassing the value of commercially available single‐crystalline Tb3Ga5O12. Compositions with a higher rare‐earth oxide content (60 mol%) than that of binary glasses facilitated the successful synthesis of Tb2O3–Dy2O3–B2O3 ternary glasses. The Verdet constant linearly increased with increasing Tb2O3 content for the glasses with 40 mol% B2O3. Results indicate that rare‐earth‐rich borate glasses are promising candidates for magneto‐optical applications in the visible region, and that the types and amounts of rare‐earth ion mainly affect these properties. [ABSTRACT FROM AUTHOR]

Classical molecular dynamics (CMD) simulations that employ analytical force fields have been commonly utilized to investigate mechanical, chemical, and thermal properties of oxide glasses owing to their superior computational efficiency. Conversely, simple functional forms limit the accuracy in modeling complicated glass structures, specifically, in alkaline borate glasses, which exhibit boron coordination numbers that vary nonlinearly with changes in glass composition and temperature. Machine‐learning potentials (MLPs), which are trained using datasets on energy and force evaluated via the density functional theory (DFT), are garnering significant attention as a novel simulation technology for enhancing the accuracy in modeling materials. Therefore, this study applied a universal MLP, PreFerred Potential (PFP) (trade‐name: Matlantis), to model sodium borate glasses, and its accuracy was verified in reproducing boron coordination and ring structures by comparing its results to available experimental data. We found that PFP can quantitatively reproduce the boron coordination change with glass composition without any empirical correction, while the boron coordination in the melts at high temperatures is overestimated, even though the qualitative variation was better estimated than CMD simulations. Furthermore, the MLP could generate many 3‐rings, unlike the analytical force‐field. Accordingly, we demonstrated superior accuracy of the MLP in modeling alkaline borate glasses, while discussing the challenges faced in reproducing the elaborated microstructures in borate glasses. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) power devices are attracting significant attention due to their outstanding stability in high-voltage, high-temperature, and highfrequency environments. To replace toxic Pb-based glass, there is an urgent need to develop Pb-free glass for SiC power device encapsulation, considering its superior electrical insulation properties and processing capabilities. Here, we developed a Bi-based glass for effective encapsulation practical of SiC power devices. By increasing the content of glass modifier BaO, the structure of bismuth borate glass can be tuned to reduce glass network density, leading to the transition of structural units from [BO4] to [BO3]. The softened temperature is reduced to 363.4°C with the BaO content increasing to 15 mol%. After encapsulating the SiC power devices using Bi-based glass, the glass demonstrated a reverse breakdown voltage of 650 V and an extremely low leakage current. Therefore, ourwork provided a route for adapting Pb-free-based low-melting glass for encapsulating SiC devices and offered potential for advanced semiconductor packaging. [ABSTRACT FROM AUTHOR]

Predicting the properties of glass based on compositional and structural information is a fundamental issue with enormous practical and industrial significance for the study of laser glass. Here we address this problem and demonstrate the application of phase diagram method in predicting the spectroscopic properties of Nd3+‐doped binary and ternary silicate, binary phosphate, and borate laser glasses from their initial congruently melting compounds. In particular, spectroscopic properties, such as effective linewidth (Δλeff) and fluorescence branching ratio (β) can be precisely predicted in all glass systems with an error less than 5%. Furthermore, a composition–structure–property database of Nd3+‐doped ternary silicate glass system is established and preliminarily applied to the composition design and explanation of commercial glass. This study provides interpretable predictions of the optical and spectroscopic properties for Nd3+‐doped laser glasses. [ABSTRACT FROM AUTHOR]

A new self‐consistent empirical potential model based on the BMP potential [Bertani et al., Phys. Rev. Mat. 5 (2021) 045602] has been developed for the simulation of multicomponent borate and borosilicate glasses. We exploited the Bayesian optimization approach to create a set of parameters for the B–O interaction, which depends on the glass composition, and in particular on the R = ([A2O]+[AEO])/[B2O3] (A = alkaline and AE alkaline‐earth ions) and K = [SiO2]/[B2O3] ratios. The obtained force field (FF) has been applied to several borate and borosilicate glass series containing, as modifier oxide, Na2O, Li2O, CaO, and MgO and tested on experimental data, such as the fraction of BO4 (N4), density, non‐bridging oxygen speciation, neutron diffraction spectra, 11B, 29Si, and 17O magic angle spinning nuclear magnetic resonance. A comparison with other interatomic potentials available in literature has also been performed. The results show that the FF reproduces well almost all the abovementioned properties, showing excellent agreement with experimental data in a wide range of compositions. [ABSTRACT FROM AUTHOR]

Hollow biphasic calcium phosphate (BCP) microspheres with different fractions of nanocrystalline hydroxyapatite (HA) and β‐tricalcium phosphate (β‐TCP) were prepared, and their in vitro and in vivo reactivity were assessed. The microspheres were prepared by reacting soluble borate glass microspheres in phosphate solutions (0.1‐ or 0.25‐M K2HPO4) with different values of pH (7–12) to produce hollow calcium‐deficient hydroxyapatite (CDHA) microspheres with Ca/P ratios that increased with solution pH. Heating the hollow CDHA microspheres to 800°C produced hollow, nanoporous BCP microspheres with ratios of nanocrystalline HA and β‐TCP that correspond to the Ca/P ratio of the CDHA precursors. Hollow BCP microspheres with a greater fraction of β‐TCP released calcium ions most quickly in a K‐acetate acidic buffer solution, consistent with their greater bioactivity in the in vivo tests. CDHA and BCP microspheres converted to nanocrystalline carbonated HA when immersed in 37°C simulated body fluid. Hollow CDHA and BCP microspheres were implanted in rat calvarial defects, and after 8 weeks, the BCP microspheres with a β‐TCP/HA ratio of 70/30 (by weight) promoted a greater fraction of new bone formation (33% ± 7%) compared to BCP microspheres with a β‐TCP/HA ratio of 44/56 (20% ± 9%) and compared to the respective CDHA precursor microspheres (17% ± 4%, 17% ± 5%). Bone formation was not observed in the subcutaneous implants of any types of these hollow microspheres, after 8 and 12 weeks, and the more reactive BCP microspheres (β‐TCP/HA = 70/30) were associated with significantly more blood vessel formation in the subcutaneous implants. These results indicate that the properties of hollow BCP microspheres can be tailored by their processing conditions and are useful as scaffold materials for tissue regeneration. [ABSTRACT FROM AUTHOR]

Borate‐based glasses have generated great interest for wound healing applications due to their ability to incorporate biologically therapeutic ions which can then be released at the site of repair attributable to their high dissolution rates. In this study, the anti‐bacterial activity and cytocompatibility of sol‐gel–derived silver‐doped borate glasses (AgBGs) of the compositional range (60)B2O3–(36)CaO–(4–x)P2O5–(x)Ag2O, where x = 0.0, 0.3, 0.5, and 1 (mol.%) were investigated, in vitro. The dose‐dependent anti‐bacterial activity of AgBGs was demonstrated against Pseudomonas aeruginosa under both planktonic conditions and pre‐formed biofilms, with up to 99.7% reduction in bacterial cell counts. Lower concentrations of ionic dissolution products from AgBGs were non‐toxic to keratinocytes, stimulating their growth and metabolic activity. Furthermore, compositions containing 0.3 and 0.5 mol.% Ag significantly accelerated the migration of keratinocytes at two different concentrations in an in vitro 2D wound healing model. In summary, these therapeutic AgBGs have demonstrated potential for accelerated wound healing. [ABSTRACT FROM AUTHOR]

Relaxation behavior is critically important for nearly all high‐tech applications of glass. It is also known as one of the most difficult unsolved problems in condensed matter physics. The relaxation behavior of glass can be described using the stretched exponential decay function exp‐t/τβ, the shape of which is governed by the dimensionless stretching exponent β. Here, a temperature‐dependent model for β(T) is proposed. The model is derived based on the Adam‐Gibbs relationship and insights from the energy landscape description of glass‐forming systems. The model captures previously known limiting values of β(T) while also providing a continuous transition between these limits. Additionally, the model captures the effects of fragility and thermal history. The model is validated with experimental data for commercial silicate glasses and a borate glass. [ABSTRACT FROM AUTHOR]

Erratum for a new self-consistent empirical potential model for multicomponent borate and borosilicate glasses Keywords: borates; borosilicate glass; molecular dynamics; structure EN borates borosilicate glass molecular dynamics structure 5104 5105 2 06/05/23 20230801 NES 230801 B Abstract b The manuscript contains a mistake in Equation (6) and an erroneous value of the B SB ij sb term of B-O interaction in Table 2. Borates, borosilicate glass, molecular dynamics, structure. [Extracted from the article]

We have fabricated CsPbBr3 perovskite quantum dots (QDs) in a multi‐component borate glass by melt‐quenching technique. Transmission electron microscopy (TEM) reveals a cubic phase CsPbBr3 crystal for QDs. As the treatment temperature or the treatment time duration increases, the photoluminescence (PL) peak shifts to long wavelength in the range of 510 to 525 nm, and the full width at half‐maximum varies in the range of 24 to 18 nm. The absorption edge shifts to low energy side in the range of 2.54 to 2.41 eV. The different photoluminescence excitation spectra (PLE) reflect the change of microstructure for different samples. The PL peak wavelength and line‐shape are independent of excitation wavelength. These results of spectra show typical exciton emission characteristics. As treatment conditions strengthens, photoluminescence quantum yield (PLQY) first increases and then decreases, having the best PLQY 86.9%. Bi‐exponential fitting curves show that short lifetime τ1 continuously decreases. Long lifetime τ2, weight for long lifetime component, and average lifetime τavg first increase and then decrease. The PLQY values are affected by both τ1 and τ2, which are relative to the crystal quality in the interior and the surface of QDs, respectively. The high PLQY value corresponds to medium treatment condition, which is attributed to a balanced effect of crystal quality in interior and the surface of QDs. [ABSTRACT FROM AUTHOR]

Oxyfluoride glass and glass‐ceramics are being studied due to the possibility of their utilization in many applications, such as thermoluminescent dosimeters, optical fibers, fluorescent concentrators, and temperature sensors. In order to improve the properties of glass, they are often crystallized. For this crystallization to be effective, knowledge and control of the structure of the starting material is required. Much work was done on silicate glass; however, a great interest exists in obtaining these kinds of materials in other matrices such as germanates, phosphates, and borates. Here, we present a structural study of some oxyfluoride borate glass with different concentrations of PbF2 by means of Nuclear Magnetic Resonance (NMR), Raman, and Fourier Transform Infrared (FTIR) spectroscopies. We also analyzed glass‐crystallization using Differential Scanning Calorimetry (DSC). The crystallization study was complemented with the use of Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED), for the purpose of identifying possible mechanisms of crystallization. Our results indicate, from the structural point of view, that the glass present groups with one or two BO4 species, such as diborate or pentaborate. The small variation in the BO4 fraction with the increase in PbF2 concentration would be an indication of the formation of F−BO3/2 species. Oxyfluoride borate glass containing BaO as a cation modifier and 30% PbF2 represents a good starting point for obtaining glass‐ceramics with a narrow size distribution of BaF2 nanocrystals. We also propose that the possible mechanism for oxyfluoride borate glass crystallization started with a separation of phases. [ABSTRACT FROM AUTHOR]

Although great advance has been made in glass science, predicting luminescence properties of laser glass poses a significant challenge for scientists due to the complex relationship between the composition, structure, and properties of the rare earth ions doped laser glasses. The development of high‐performance laser glass usually relies on intuition and trial‐and‐error. Recently, with the proposal of the materials genome engineering, the "glass genome" has also attracted much attention. Here, the structure of the Nd3+ doped B2O3‐Li2O laser glasses was analyzed using Fourier transform infrared spectra and nuclear magnetic resonance, revealing that the glass contains similar glass‐forming ion‐centered coordination polyhedron structure groups to the neighbor congruent glassy compounds. The structure and properties of glass largely depend on the neighbor congruent glassy compounds. Therefore, the structure and luminescence properties of Nd3+ doped B2O3‐Li2O and B2O3‐MgO‐Li2O laser glasses can be quantitatively predicted via the neighbor congruent glassy compounds. The predictive values are in good agreement with the experimental data, which indicates that our approach is an effective way to predict the structure and luminescence properties of Nd3+ doped borate laser glasses. [ABSTRACT FROM AUTHOR]

Engineering borate glass structure by simple compositional modification is essential to meet the particular demands from both industrial and photonic research communities. In this article, we demonstrate how the mixing of Li2O with Na2O, K2O, or Cs2O influences the relative abundance of 3‐ and 4‐coordinated borons in the glass network, as exhibited by nuclear magnetic resonance (NMR) and Raman spectra. A systematic study is given of the alkali mixing effect on the glass properties including: glass transition temperature, microhardness, density, refractive index, and particularly the near‐infrared photoluminescence properties (eg, bandwidth and lifetime) of Er3+ which has been barely studied in mixed alkali borate glasses. It is interesting to note that the glass transition temperature, refractive index and emission lifetime of Er3+ manifest mixed alkali effect, in sharp contrast with microhardness, density, and emission bandwidth which vary monotonically upon the alkali mixing. The possible causes for the differences are discussed in the light of the compositional dependence of boron species and nonbridging oxygen upon alkali mixing. [ABSTRACT FROM AUTHOR]

Lithium borate (LB) glasses and crystals with x = Li/(Li + B) = mole fraction of Li2O of 0.2–0.5 have been synthesized by the quenching method. The thermodynamics of these materials were analyzed by high‐temperature oxide melt solution calorimetry. The formation enthalpies from oxides of glasses range from −33.6 to −67.3 kJ/mol and those of crystals range from −42.1 to −77.4 kJ/mol, where compositions are given on the basis of one mole of (Li2O + B2O3). The formation enthalpies of both glasses and crystals become more negative with increasing Li2O mole fraction up to 0.5. The enthalpies of formation of glasses can be fit over the entire composition range (0 < x < 1) by a quadratic polynomial). The vitrification enthalpies were derived for x = 0.2 to 0.5 and ranged from 8.5 to 17.6 kJ/mol. The main factors controlling energetics are the strongly exothermic acid–base reaction between the network former (B2O3) and the network modifier (Li2O) and the formation of tetrahedrally coordinated boron in the glasses and crystals. [ABSTRACT FROM AUTHOR]

Bismuth-doped (Bi) glasses and fibers have raised considerable attention for broadband emission and tunable fiber lasers in the near infrared (NIR) region. However, they suffer from low efficiency and it remains challenging to enhance Bi NIR emission. Here, we propose a facile way to enhance and tune the Bi NIR emission by adjusting optical basicity and modulating the boron and aluminum coordination in borate glasses. We find that BO4 and AlO5 species favor Bi NIR emission, right followed by the analyses of static emission spectra, the Fourier transform infrared (FT-IR), and nuclear magnetic resonance (NMR) spectroscopy. Furthermore, abnormal Bi NIR luminescence phenomenon and boron anomaly were observed, which are attributed to the synthetic effect of B and Al coordination transformation. Besides, we find that BO4 tetrahedron plays a major role in enhancing Bi NIR emission at low Al content, while AlO5 hexahedron group will dominate at high Al concentration. Our investigation may give an insight into the luminescent behaviors of Bi in borate glasses and contribute to improving the performance of Bi-doped fiber and fiber lasers in future. [ABSTRACT FROM AUTHOR]

Rare-earth-doped oxyfluoride germanate and borate glasses were synthesized and next studied using spectroscopic methods. Influence of fluoride modifier on luminescence properties of rare earths in different glass hosts was examined. The excitation and emission spectra of Pr3+ and Er3+ ions in the studied glasses were registered. The emission spectra of Pr3+ ions in germanate and borate glasses are quite different and depend strongly on the glass host. In samples doped with Er3+ ions emission bands located around 1530 nm corresponding to the main 4I13/2→4I15/2 laser transition were registered, independently of the glass host. Quite long-lived near-infrared luminescence of Er3+ ions was observed for germanate glasses with low BaF2 content, while in borate glass systems influence of barium fluoride on luminescence lifetimes is not so evident. The Judd-Ofelt calculations were used in order to determine quantum efficiencies of excited states of rare-earth ions in germanate and borate glasses. [ABSTRACT FROM AUTHOR]

A series of glasses composed of xB2O3-8Al2O3-(90-x)Na2O-R2O3 (x = 65, 70, 75, 80, 85; R = Dy3+, Tb3+, Sm3+) were prepared through melt-quenching. Structural evolution was induced by varying the glass composition. Increasing the glass network former B2O3 enhanced the luminescence of rare-earth ions, as observed in the emission spectra. The mechanism of the glass structural evolution was investigated by the NMR spectra analysis. The dispersant effect of the glass structure was believed to promote the better distribution of the rareearth ions in the matrix and reduced the concentration quenching between them. The relationship between the glass structure and its optical properties was established. [ABSTRACT FROM AUTHOR]

The solubility of Co3O4, Cu2O, CuO, NiO, and Mn2O3 in molten B2O3 and Na2O-2B2O3 has been studied at a temperature of 900°C under static conditions. The concentration of the dissolved metal oxides was determined by X- EDS and XPS elemental analysis. Uniformity of metal distribution has been confirmed using X- EDS and backscatter electron image mapping. It was found that the solubility of all metal oxides increased significantly with Na2O content in the B2O3 solvent. The impact of a temperature increase of 150°C and the influence of K2O doping were evaluated and found to not cause any significant change. [ABSTRACT FROM AUTHOR]

The field strength of modifier cations in boron-containing oxide glasses has important but complex effects on boron coordination, and has long been known to have major effects on glass and liquid properties. With well-constrained compositional and fictive temperature information in three binary borate glass series, we report how different modifier cations ( Na+, Ba2+, Ca2+) affect boron coordination (11B MAS NMR), as well as glass transition temperatures and configurational heat capacities ( DSC). Using estimated reaction enthalpies for converting a [4]B to a [3]B with an NBO from previous studies, we compare boron coordinations in glasses with different modifier cations on an isothermal basis. Temperature and modifier cation effects can thus be isolated. At low modifier contents [ R = ( Na2, Ca, Ba) O/ B2 O3<0.45], N4 is systematically higher in the order Na> Ba> Ca, suggesting the enhanced stabilization of NBO for the divalent cations, especially for the smaller Ca2+. At higher R values, N4 for Na borates drops below values for Ca and Ba borates. The trend in N4 with modifier field strength reverses at high R values (~ R > 0.7), with Ca > Ba > Na. The transition may be related to the enhanced stabilization of [4]B-O-[4]B groups by higher field strength cations in NBO-rich glasses in which boron is the primary network component. [ABSTRACT FROM AUTHOR]

Transparent Bi2 ZnO B2 O6 glasses were prepared by melt quenching technique. The thermal behavior of the glasses was studied using differential thermal analysis ( DTA), structure by X-ray diffraction ( XRD) and the morphology is observed using scanning electron microscope ( SEM) and optical polarization microscope. Crystallization kinetics has been studied under isothermal and non-isothermal conditions by using DTA. Two exothermic peaks were observed in the non-isothermal DTA curve and XRD analysis confirms that the first exothermic peak belongs to crystallization of β- BiB3 O6 phase whereas the second exothermic peak belongs to formation of Bi2 ZnO B2 O6 phase. The obtained Avrami parameter indicates that the glass heat-treated at its first crystallization temperature leads to surface crystallization whereas the glass heat-treated at second crystallization temperature shows three-dimensional bulk crystallization. The glasses heated at intermediate temperatures of the exothermic peaks exhibit both the β- BiB3 O6 and Bi2 ZnO B2 O6 phases indicating the presence of surface and bulk crystallizations. The glass morphological study also confirms the same behavior. [ABSTRACT FROM AUTHOR]

We reevaluated nine parameters of glass stability ( GS) against crystallization determined from differential scanning calorimetry ( DSC) experiments to predict the glass-forming ability ( GFA) of oxide liquids on cooling. Then, borate glasses were prepared and tested, covering the Li2 O- B2 O3 system with 20.0-66.7 mol% lithia. The glasses were prepared from both commercial chemical and powders, obtained by a solution method. The GS parameters were calculated using characteristic glass transition, crystallization, and melting peaks of DSC thermograms. We found that seven stability parameters give similar trends for compositions up to 33.3 mol% lithia, where, as we expected, GS significantly decreases with lithia content. Thereafter, up to 66.7 mol% lithia, GS shows a broad shallow maximum, but is approximately constant indicating that, surprisingly, composition does not significantly affect the GFA in this wide compositional range. This result qualitatively agrees with our successful experience of preparing glasses with compositions up to 74 mol% lithia and corroborates the adequacy of simple DSC tests to comparatively gauge the GS and GFA of glass-forming liquids. [ABSTRACT FROM AUTHOR]