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Phosphate-based glasses (PBGs) in the CaO–Na2O–P2O5 system have diverse applications as biomaterials due to their unique dissolution properties. A reactive force field (ReaxFF) has been developed to simulate these materials at the atomic level. The ReaxFF parameters of PBGs, including the interaction between phosphorus and calcium atoms, have been developed using a published code based on genetic algorithms. The training data, including the atomic charges, atomic forces, bond and angle parameters, and different differential energies, are chosen and measured from static quantum-mechanical calculations and ab initio molecular dynamics of PBGs. We did different short- and medium-range structural analyses on the bulk simulated PBGs with different compositions to validate the developed potential. Radial and angular distribution functions and coordination numbers of network formers and modifiers, as well as the network connectivity of the glass, are in agreement with experimental and previous simulations using both shell-model classical force fields and ab initio simulated data; for example, the coordination number of phosphorus is 4.0. This successful development of ReaxFF parameters being able to describe the bulk PBGs enables us to work on the dissolution behavior of the glasses, including the interaction of water molecules with PBGs, in future works. [ABSTRACT FROM AUTHOR]

Several glassy oxide semiconductors exhibit large electron mobilities; however, these oxides may not be considered environmentally friendly because of their toxicity. Herein, we report on the electrical conduction of iron oxide-containing bismuth sesquioxide borate glasses that are not toxic and show ohmic transport in the temperature range of 100–400 °C. The dominant carrier is the electron, which is revealed by the signs of Hall and Seebeck coefficients, without sign anomalies. The Hall mobility is ∼0.1 cm2/(V s), and the carrier density is ∼6 × 1015 cm−3 at 400 °C. The Seebeck coefficient is approximately −500 μV/K at 388 °C. The carriers might be generated by charge transfer between Fe2+ and Fe3+ substituted in the glass, and they exhibit thermally activated hopping-type electronic conduction. The oxide glass can be used as a glass thermistor for a temperature range of 100–400 °C. [ABSTRACT FROM AUTHOR]

As a distinguished luminescent matrix, rare earth (RE)-doped glass has garnered considerable attention across lighting, display, laser, and related domains. Nonetheless, the limited luminescent efficiency of such glass imposes constraints on its extensive utilization. In addressing this challenge, we have developed a novel formulation involving heavily Eu3+-doped black talc glass, boasting exceptional optical characteristics. Structural examination has validated the successful synthesis of the parent glass matrix comprising [SiO 4 ] and [AlO 4 ] units. With the escalating of Eu3+ doping concentrations, the glass manifested an upward trend in both density and refractive index. Under the excitation of 393 nm light, the glass exhibited strong red light emission, demonstrating a high internal quantum efficiency (IQE) of up to 84.67 %, surpassing markedly other Eu3+-doped glass variants. Furthermore, even under elevated temperatures reaching 150 °C, the glass retained 86.2 % of its luminescent intensity at room temperature, indicative of superior thermal resilience vis-à-vis alternative glass systems. As a proof-of-concept, we encapsulated a white light-emitting diode (W-LED) assembly employing a 395 nm LED chip, Eu3+-doped glass, BaMgAl 10 O 17 :Eu2+ blue phosphor, and Ba 2 SiO 4 :Eu2+ green phosphor. The resultant device exhibited favorable chromaticity coordinates (0.3566, 0.3994), boasting a correlated color temperature (CCT) of 4791K and a high color rendering index (CRI) of 91. In summary, this investigation employs black talc ore to synthesize luminescent glass, thereby not only diversifying the application scope of black talc but also augmenting its additional value, while notably enhancing the luminescent efficiency of the glass through heavy Eu3+ doping. Through empirical validation, the significant potential benefits of Eu3+-doped black talc glass in the realm of W-LED lighting were convincingly demonstrated. [ABSTRACT FROM AUTHOR]

This work provides new insights into the nature of the polaronic transport in xV2O5–(100−x)P2O5, 41 ≤ x ≤ 89 mol% glasses from analysis of their conductivity over a wide range of frequencies and temperatures, and correlation of the electrical parameters to the structural models of these materials. The results show that the linear increase in direct current (DC) conductivity with the increase in V2O5 could be related to the formation of a vanadate subnetwork, which is characterized by a length distribution of V–O bonds and variations in linkages between different vanadate units. Such a structurally complex network offers multiple conduction pathways which are favorable for polaron hopping. The Summerfield scaling of conductivity spectra reveals a temperature‐invariant mechanism of polaron transport for all glasses and the same local structural environment of polarons at higher V2O5 contents due to the same ratio of vanadate units present in the network. Also, this study highlights the similarities and differences in the nature of the polaronic transport of vanadate–phosphate glasses and other polaronically conducting phosphate glasses containing WO3, MoO3, and Fe2O3, and pins down a pivotal role of the glass structure in electrical processes in these materials. [ABSTRACT FROM AUTHOR]

This study delves into the impact of substituting Nd 2 O 3 for Na 2 O in Barium–Boron-Phosphate glasses, aiming to enhance their mechanical strength, optical characteristics, and radiation shielding efficacy. Glasses with a composition of 50B 2 O 3 + 20P 2 O 5 + 20BaO + (10-x)Na 2 O + xNd 2 O 3 (x = 0, 1, 2, 3, 4 mol%) were synthesized and characterized. The findings indicate that as the Nd/Na ratio increases, the density of the glass also rises within the range of 3.77–4.23 g/cm3. Moreover, the addition of Nd leads to notable alterations in the optical characteristics of the resulting glasses. Specifically, there is a shift observed in the UV absorption edges, coupled with a noticeable increase in absorption at visible wavelengths. Moreover, Nd 2 O 3 addition reduced the Urbach energy (from 0.6018 to 0.2239 eV for Nd0-Nd4) and the optical band gap indicating improved electronic structure and decreased disorder. The mechanical properties studied using the Makishima-Mackenzie model show As the replacement ratio of Nd 2 O 3 increases, there is a noticeable improvement in the glass's mechanical robustness. Importantly, Glasses with high Nd/Na ratio in their composition exhibit enhanced radiation shielding capabilities, evidenced by increased mass attenuation coefficients and effective removal cross-sections for photons and fast neutrons, respectively. These findings suggest that Nd 2 O 3 -doped glasses offer a promising pathway for developing superior radiation shielding materials with tailored properties for diverse applications in nuclear facilities, medical devices, and space exploration equipment. [ABSTRACT FROM AUTHOR]

Erbium-doped glass microsphere laser systems hold significant promise in the applications of bio-medicine and optical fiber sensing. However, their development has been hindered by the relatively high laser pump threshold. In this study, we proposed a unique dual microsphere system where two microspheres are affixed to a single-mode fiber taper and achieved a remarkably low lasing threshold of 19 μW for single-mode laser emission at 1544 nm. This is in sharp contrast with the lasing threshold of 56 μW observed in single microspheres. Our findings represent a significant achievement in the development of low-threshold, compact infrared laser sources for emerging applications in photonics. [ABSTRACT FROM AUTHOR]

Phosphate glasses have garnered significant attention as host materials for various laser applications due to their high rare‐earth ion solubility, large stimulated emission cross‐section, and low nonlinear refractive index. Modification of phosphate glass composition is feasible through poly‐anion substitution, leading to poly‐anionic glasses with unique properties. This study explores the glass‐forming regions (GFRs) of AlF3‐R2SO4‐M(PO3)2‐based poly‐anionic fluoro‐sulfo‐phosphate (R/M‐FSP) glasses, a promising class of ionic glasses. Theoretical GFRs are predicted using a thermodynamic approach and then validated through a few experiments. The experimental GFRs range from K/Ba‐FSP > Na/Ba‐FSP > Li/Ba‐FSP > K/Sr‐FSP > Na/Sr‐FSP > Li/Sr‐FSP, with wider areas observed under lower cation field strength. Notably, the K/Ba‐FSP glass system exhibits high anti‐crystallization stability (approximately 140°C) and a low nonlinear refractive index (1.43 × 10–13–1.83 × 10–13 esu), advantageous for high‐power laser operations. Furthermore, a comparative study among K/Ba‐FSP glasses elucidates the general principles of manipulating glass structure and physical properties through compositional variation. [ABSTRACT FROM AUTHOR]

Bismuth (Bi)‐doped glass fibers are being developed into next‐generation broadband amplifiers and tunable lasers. Yet, the well‐developed Bi‐doped fiber devices only realize silica‐based optical fibers prepared by the modified chemical vapor deposition method, which faces challenges such as low doping concentration, high cost, intricate device structure, and high preparation difficulty. Here, a novel highly Bi‐doped multicomponent phosphate glass was developed. The high ion solubility of this phosphate glass facilitates achieving a Bi doping concentration of 8 mol%. The introduction of aluminum nitride (a new reducing agent) can create a local reducing environment, further increasing the concentration of low‐valence near‐infrared (NIR) active Bi ions. Furthermore, the resulting enhanced highly Bi‐doped multicomponent phosphate glass with efficient 900–1600 nm NIR emission can be drawn into corresponding optical fibers by a rod‐in‐tube method. Broadband NIR amplified spontaneous emission with a 3 dB bandwidth of 275 nm was achieved in this new fiber. As far as we know, this is the first successful preparation of Bi‐doped multicomponent phosphate glass fiber. Our results indicate that this fiber will be a powerful alternative to Bi‐doped silica‐based fibers for the preparation of related Bi‐doped fiber devices. [ABSTRACT FROM AUTHOR]

Gallium fluoride phosphate glasses feature low refractive index, high energy radiation resistance, wide transmission range, and favorable emission characteristics of rare‐earth dopants. For the development of optimized glass compositions, a fundamental understanding of these properties in terms of glass structure is sought. We report nuclear magnetic resonance (NMR) structural studies of glasses in the system xGa(PO3)3–(40 − x)GaF3–20BaF2–20ZnF2–20SrF2 (x = 5, 10, 15, 20, and 25 mol%). 31P NMR results with 71Ga recoupling show that the network structure is dominated by P–O–Ga linkages, and no P–O–P linkages exist. 71Ga NMR results show that Ga is mainly six‐coordinated featuring a mixed fluoride/phosphate coordination. Quantitative estimates of this ligand distribution around gallium were obtained by 71Ga{31P} spin echo double resonance (REDOR) measurements. Photophysical properties suggest changes in the Eu(III) ligand distribution toward a fluoride‐dominated environment at low P/F ratio while the glass network is largely sustained by bridging oxygen atoms via P–O–Ga linkages. [ABSTRACT FROM AUTHOR]

In recent years, glass anodes have been widely studied. However, self‐crystallization often occurs during glass preparation, which leads to a reduction in the cycle stability of the glass anode. In this work, SnO–P2O5–MnO2 glass anode materials were prepared using the melt‐quenching method. By increasing the concentration of MnO2, the specific capacity (after 800 cycles) of the glass anode was increased by 62%, from 234.9 to 381.3 mAh g−1. The result indicates that the introduction of MnO2 makes the glass structure more compact and suppresses the glass's ability of self‐crystallization, which is beneficial for the long‐cycle performance of lithium‐ion batteries. In addition, with the introduction of MnO2 in glass, manganese–tin synergistic discharge disperses the internal stress during the alloying process, which further enhances the cycling stability of the glass anode. This research is to propose a new reference for improving the cycle life and specific capacity of glass anode materials. [ABSTRACT FROM AUTHOR]

Broadband near‐infrared (NIR) emitting materials have gained considerable attention for their applications in lighting, displays, sensing, bio‐imaging, and optical amplification. Recently, numerous excellent broadband NIR emitting materials are developed by introducing Cr3+, Bi+, or Ni2+ ions to various hosts. However, there is a notable absence of reports on ultra‐broadband NIR emitters spanning the entire telecommunication window as well as the NIR‐I (700–1000 nm) and NIR‐II (1000–1700 nm) biological windows activated by vanadium ions. Herein, the study presents, for the first time to the best of the knowledge, ultra‐broadband NIR emission ranging from 850 to 1600 nm (peaking at ≈1000 nm) at room temperature in vanadium‐doped phosphate glass. Detailed spectra and microscopic structure analysis reveal that two V3+‐emitting centers predominantly contribute to the ultra‐broadband emission, corresponding to 3T2(3F)→3A2(3F) spin‐allowed and 3T2(3F)→1E(1D) spin‐forbidden electron transitions of tetrahedrally coordinated V3+ ions. Notably, the tunability of NIR emission peak is demonstrated by adjusting the local glass structure or the vanadium doping content. Moreover, glass‐converted light‐emitting diodes (gc‐LEDs) are fabricated from vanadium‐doped glass, and the potential applications are demonstrated. The work opens new avenues for the design and fabrication of broadband NIR‐emitting materials and opto‐electronic devices. [ABSTRACT FROM AUTHOR]

YVO4, YPO4 and YV1-xPxO4 phosphors with various Tb3+ doping concentrations were prepared by high-temperature solid-state method. Differential scanning calorimetry (DSC) measurements were conducted to evaluate the chemical reactions during synthesis process, determining 1 350 °C as the optimal synthesis temperature. X-ray diffraction (XRD) analysis of the synthesized materials confirmed a tetragonal crystal structure for all samples. The luminescent properties of the mentioned phosphors at room temperature were investigated. Under ultraviolet excitation, luminescence in YVO4 : Tb3+ predominantly arises from the 5D3→7FJ(J = 6, 5, 4, 2) transitions, resulting in blue emission. The introduction of P element modified the crystal field environment in YV1 - xPxO4 :Tb3+, enhancing multi-phonon relaxation (MPR) and cross-relaxation (CR) between 5D3 and 5D4 energy levels. With increasing P element content, the emission gradually shifted towards 5D4→7FJ' (J' = 6, 5, 4, 3), displaying blue, cyan, and green emissions. In YPO4 : Tb3+, higher doping concentrations enhanced cross relaxation between 5D3 and 5D4 energy levels of Tb3+, leading to weakened 5D3 luminescence and intensified 5D4 luminescence. Fine- tuning the doping concentration enabled the control of luminescence from blue to green. In conclusion, by adjusting the matrix composition and doping concentration, the blue-green luminescence modulation of Tb3+ -doped vanadium phosphate system can be achieved. [ABSTRACT FROM AUTHOR]

CsPbX 3 (X = Cl/Br, Br, Br/I, I) perovskite quantum dots (QDs) glasses have enormous application potential in the field of long wavelength pass (short wavelength cutoff) filters. In this work, the CsPbX 3 (X = Cl/Br, Br, Br/I, I) QDs doped with Se4+ were prepared in the borogermanate glass matrix. To quench strong exciton emission of QDs, the CsPbX 3 (X = Cl/Br, Br, Br/I, I) perovskite QDs glasses were doped with Se4+ at different concentrations of 0, 0.05 %, 0.1 % and 0.2 %, respectively. The nanocrystal structure, transmittance, optical density, photoluminescence (PL), PL excitation and PL decay have been investigated. The working wavelength of filters has been extended to wide range from 440 nm to 650 nm. The samples have large optical density in cutoff region, excellent steepness in the transition region, and high transmittance in transmission region. As Se4+ concentration increases, the PL intensity is quenched and the PL lifetime is decreased obviously for CsPbX 3 QDs glasses, whereas the absorption and transmittance characteristics for filters are less affected. The quenching mechanism is attributed to nonradiative recombination by deep energy level traps. The Se4+ doped CsPbX 3 QDs glasses can meet requirements for the long wavelength pass filters. [ABSTRACT FROM AUTHOR]

Here we describe the synthesis of a compositional series of metal–organic framework crystalline-inorganic glass composites (MOF-CIGCs) containing ZIF-8 and an inorganic phosphate glass, 20Na2O–10NaCl–70P2O5, to expand the library of host matrices for metal–organic frameworks. By careful selection of the inorganic glass component, a relatively high loading of ZIF-8 (70 wt%) was achieved, which is the active component of the composite. A Zn⋯O–P interfacial bond, previously identified in similar composites/hybrid blends, was suggested by analysis of the total scattering pair distribution function data. Additionally, CO2 and N2 sorption and variable-temperature PXRD experiments were performed to assess the composites' properties. [ABSTRACT FROM AUTHOR]

The progression of optical materials and their associated applications necessitates a profound comprehension of their optical characteristics, with the Judd–Ofelt (JO) theory commonly employed for this purpose. However, the computation of JO parameters (Ω2, Ω4, Ω6) entails wide experimental and theoretical endeavors, rendering traditional calculations often impractical. To address these challenges, the correlations between JO parameters and the bulk matrix composition within a series of Rare-Earth ions doped sulfophosphate glass systems were explored in this research. In this regard, a novel soft computing technique named genetic expression programming (GEP) was employed to derive formulations for JO parameters and bulk matrix composition. The predictor variables integrated into the formulations consist of JO parameters. This investigation demonstrates the potential of GEP as a practical tool for defining functions and classifying important factors to predict JO parameters. Thus, precise characterization of such materials becomes crucial with minimal or no reliance on experimental work. [ABSTRACT FROM AUTHOR]

The current research focuses on improving some of the physical and radiation properties of barium zinc phosphate glass containing lead oxide. The Makishima-Mackenzie model evaluates the elastic parameters. The XCOM database simulation predicts the shielding properties. Furthermore, the glass composition and the simulated X-ray or gamma-ray energy predict the shielding behavior. The optimal thickness for all glass samples to achieve a 90% reduction in intensity at an energy of 59.54 keV is 5.2 mm. These glasses have great potential as materials for shielding against gamma and X-rays. [ABSTRACT FROM AUTHOR]

In this work, novel Mn2+‐doped transparent NaYP2O7 glass–ceramics were prepared through melt‐quenching and subsequent thermal treatment. The surface crystallization method was confirmed based on the differential scanning calorimeter, X‐ray diffraction, and scanning electron microscope characterization. As the increase and prolong of the heat‐treatment temperature and time, the crystallinity of the NaYP2O7 glass–ceramics increases, while the transmittance gradually decreases. The optimal heat‐treatment regime is identified to be crystallized over 4 h at 580°C based on the crystallinity and transmittance. Under the excitation of 408 nm, both the Mn2+‐doped precursor glass and glass–ceramic crystallized at 580°C for 4 h generate a broad emission at 620 nm (4T2(g)→6A1(s)) with a full width at half‐maximum (FWHM) of ∼107 nm. The glass–ceramics exhibit higher emission intensity and longer decay lifetime than that of precursor glass with the aid of the low phonon energy NaYP2O7 crystals. The Mn2+‐doped glass–ceramic exhibits stable orange‐red luminescence with the chromaticity coordinates of (0.568, 0.428), low correlation color temperature of 1 800 K, high color purity of 98.88%, and low thermal quenching (70% at 373 K of the initial intensity at 298 K). The above results indicate that Mn2+‐doped transparent NaYP2O7 glass–ceramics have promising potential for orange‐red color display devices. [ABSTRACT FROM AUTHOR]

Next‐generation nuclear reactor technologies such as the molten salt reactor utilize alkali metal fluoride salts as both fuel and coolant. In the present study, the suitability of iron phosphate glass (IPG) as a vitrification matrix for alkali metal fluoride (NaF, CaF2) and simulated fission product loaded fluoride (NdF3, CeF3, SmF3) waste has been explored. The structural change in the metal fluoride–loaded IPG has been analyzed thoroughly using Raman and fourier transform infrared (FTIR) spectroscopy. Thermal analysis showed that the stability and glass forming ability of IPG improved upon loading the same with various mixed metal fluorides. Mössbauer data and X‐ray absorption spectroscopy at Fe K‐edge explored the minute changes in the local structure. The effect of radiation emanating from radioactive wastes in the fluoride‐loaded IPG has been scrutinized via 4.5 MeV proton beam irradiation. Our study firmly establishes the applicability of IPG as suitable vitrification matrix for radioactive metal fluoride–loaded nuclear wastes. [ABSTRACT FROM AUTHOR]

The present work reports on the structural and spectroscopic properties of Pr3+ doped ZnS nanoparticles in silicate glasses prepared by sol–gel technique. Structural characterization was performed by X-ray diffraction, Fourier-transform infrared, scanning electron microscopy and transmission electron microscopy. The structural studies reveal the presence of nanosized in the amorphous silica glass. Spectroscopic studies were performed through absorption and photoluminescence (PL) techniques. The radiative parameters such as transition probability (Aed), radiative lifetimes (τR), and branching ratios (βR), the Judd–Ofelt intensity parameters Ωλ were determined from the absorption spectra of the prepared samples. The increase absorption as well as PL intensity was observed. This enhanced intensity is observed due to the effective increased in oscillator strength of Pr3+ doped ZnS. We observed strong stimulated emission cross-sections for the transition 3P0 → 3H6, at 614 nm. It may be useful for good lasing material in reddish-orange region. CIE chromaticity coordinates were also evaluated from the emission spectra of each glass. The development of visible reddish-orange lasers may be effectively facilitated by SiZPr1.5 glass, as indicated by the observed emission cross-sections and CIE chromaticity coordinates. [ABSTRACT FROM AUTHOR]

This paper reports white solid-state lighting potential of gold nanoparticles-embedded Dy3+-doped Li2CO3–SrO–ZnO–B2O3 glasses prepared using melt quenching. The produced materials undergo characterizations using various instrumentations to assess the sensitivity of changing AuNP concentrations on their emission characteristics. XRD phase analysis established that the samples were glasses. TEM analysis shows AuNPs, whereas EDX spectroscopic analysis confirmed the inclusion of precursor elements into the glasses. The thermal stability, Hruby parameter, and glass-forming ability are 146–156 °C, 1.27–1.39 and 66–0.65 respectively. The optical absorption spectra of the glasses are consistent with Dy3+ transitions, while the surface plasmon resonance band fits the AuNPs characteristics band. The emission spectroscopic analysis reveals intensification factors of 1.52, 1.84, and 1.14 for 6H15/2, 6H13/2, and 6H11/2 transitions. The Judd–Ofelt evaluation was made to support the experimental spectroscopic data. The CIE coordinates were traced to cool white color field with purity of 15.64–7.79% and CCT values of 5491–5437 K. The achieved excellent thermal properties, enhanced emission, and colorimetric properties, including color purity and natural daylight (cool) correlated color temperature (CCT) values, are advantageous for white solid-state lighting applications. [ABSTRACT FROM AUTHOR]

The glass set, with varying compositions of (1-x) (0.659 P 2 O 5 , 0.095 ZnO, and 0.244 PbO), was used to investigate longitudinal ultrasonic attenuation at different frequencies (2 and 14 MHz) and different temperatures (120 and 300 K). The glass samples contained different mole percentages of Nd 2 O 3 , specifically x = 0.00, 0.0046, 0.0092, 0.0138, and 0.0271. Based on the glass construction and switching frequency in well-defined broad absorption curve reaches its highest points at different temperatures. These peaks shifted to higher temperatures, indicating a relaxing mechanism, as the overall frequency increased. A thermally driven relaxation process led to the development of an approach, that the activation mechanism's average energy was mainly influenced by the mole percent content of Nd 2 O 3. The observed diminish of the acoustical energy of activation worth's, quantifiably expressed in terms of the diminished amount of oxygen atoms moving at a double-well potential, that was determined based on the number of loss centers. Such decrease in average activation energy was correlated with the increase in; Bulk elastic modulus, linear expansion coefficient, glass transition temperature and average bond dissociation energy with Nd 2 O 3. [ABSTRACT FROM AUTHOR]

Featured Application: The materials studied may be used in the radioactive waste vitrification process. Additionally, the proposed simulation method may be useful in optimizing glass composition and predicting the glass elements migration. Among the many possible applications of iron phosphate glasses, one of them is that they are promising materials in waste vitrification, particularly for radioactive waste. In vitrified form, waste elements should be permanently immobilized in a glass network as they are susceptible to harsh environmental conditions. The self-diffusion of the vitrified material species may limit the potential usefulness of the glasses. This paper presents the possibility of using molecular dynamics simulations to study this process and the substitution of SrO into an iron phosphate glass network. It was evidenced that the self-diffusion mechanism differed significantly depending on whether the glass was in a solid or liquid state. The proposed method also offered a relatively easy prediction of glass characteristic temperatures, such as transformation and flow. We also observed, and here describe, an aggregation process of the glass elements that may drive their crystallization. The obtained results are discussed in light of the experimental and theoretical structural feature literature data. [ABSTRACT FROM AUTHOR]

Abstract The progression of optical materials and their associated applications necessitates a profound comprehension of their optical characteristics, with the Judd–Ofelt (JO) theory commonly employed for this purpose. However, the computation of JO parameters (Ω2, Ω4, Ω6) entails wide experimental and theoretical endeavors, rendering traditional calculations often impractical. To address these challenges, the correlations between JO parameters and the bulk matrix composition within a series of Rare-Earth ions doped sulfophosphate glass systems were explored in this research. In this regard, a novel soft computing technique named genetic expression programming (GEP) was employed to derive formulations for JO parameters and bulk matrix composition. The predictor variables integrated into the formulations consist of JO parameters. This investigation demonstrates the potential of GEP as a practical tool for defining functions and classifying important factors to predict JO parameters. Thus, precise characterization of such materials becomes crucial with minimal or no reliance on experimental work.

This work reports the water induced discoloration phenomenon caused by space-confined effect in borophosphate glass. The CsPbBr 3 nanocrystals grown in borophosphate glass could destroy/recrystallize via the dual-switch process, which is water adhesion and water separation. Finally, an anti-counterfeiting strategy is designed to realize optical information encryption via adopting screen-printing technology. [Display omitted] Due to the sensitivity to water, the all-inorganic CsPbBr 3 nanocrystals have been widely applied in information encryption with spatial dimensions. However, the absence of time-dimension information limits the information capacity for the application of CsPbBr 3. In this work, the CsPbBr 3 nanocrystal was combined with water-sensitive borophosphate glass, achieving decomposing/recrystallization of CsPbBr 3 nanocrystal with multi-dimension. The addition of SiO 2 confirms that the collapse of the borophosphate glass network structure causes the exposure of the CsPbBr 3 nanocrystals. The decomposition and recrystallization mechanism of CsPbBr 3 nanocrystals in glass-ceramics upon encountering water has been verified. Finally, an information encryption strategy, using the mixture of CsPbBr 3 glass ceramic and sodium carboxymethylcellulose as ink, is designed via adopting screen-printing technology, which not only provides a new idea for the preparation of CsPbBr 3 nanocrystals, but also establish a new avenue for the information encryption technology. [ABSTRACT FROM AUTHOR]

The present work is involved in the synthesize, characterization and evaluating the role of CuO on physical, structural and optical properties of 45P 2 O 5 -(55-x)Na 2 O-xCuO (x = 0, 1.0, 3.0 and 5.0 mol%) compositions. The as-synthesized samples are characterized by various experimental techniques such as XRD, FTIR, Raman and UV visible spectroscopy to study their suitability for laser and non-linear optical applications. The density of glasses increases whereas molar volume decreases from with the doping of CuO in place of Na 2 O. The amorphous nature of the prepared samples is confirmed by X-ray pattern. FTIR and Raman spectra confirm the presence of metaphosphate (Q2) and orthophosphate (Q0) structural units in the prepared glass samples which confirms that the glass network become more polymerised with the addition of CuO in place of Na 2 O. The optical band gap increases from 1.94 to 4.11 eV whereas refractive index decreases from 2.76 to 2.14 with increasing doping of CuO. The molar refraction decreases while metallization criteria increase with CuO doping. This glass material demonstrates promising potential for applications in non-linear optics. [ABSTRACT FROM AUTHOR]

Titanium dioxide-enriched phosphate glasses are esteemed for their applicability in the biomaterial area, yet the investigation into the influence of TiO 2 on the crystallization dynamics of glass melts and the spinnability of sodium-calcium-magnesium phosphate glasses remains unclear. To elucidate these effects, sodium-calcium-magnesium phosphate glasses with 0, 5, and 10 mol% of TiO 2 have been prepared using the melt-quenching method, and glass fibers were drawn from the correspondent glass melts. FTIR and Raman spectroscopy have disclosed that the introduction of TiO 2 induces a depolymerization in phosphate network, causing a transition from Q2 species to Q1 units, and reduction in both the theoretical network connectivity (NC theor) and the average chain length (n theor). Meanwhile, the interposition of TiO 2 also gives rise to the replacement of P–O–P linkages with P–O–Ti bonds, along with the formation of [TiO 5 ] groups. This structural transformation resulted in the increase in molar volume and the coefficient of thermal expansion (CTE), concurrently lowering the glass transition and softening points. Evidently, the TiO 2 -free glass exhibited crystallization across a temperature range spanning from its transition to the liquidus temperature. However, the introduction of TiO 2 and the subsequent formation of P–O–Ti bonds effectively inhibited crystallization, which is favorable for drawing glass fibers. Analyses of viscosity-temperature relationships using various rheological models suggested that TiO 2 raises fragility for all glasses, suggesting a more "open" structure in the glass melts, which can be supported by the increment in free volume. The m-D diagram failed to describe the enhancement in spinnability imparted from TiO 2. While, the quantitative fiber spinnability index (K fib) increases with higher TiO 2 content, as a successful indicative of an improved ability to form fibers. [ABSTRACT FROM AUTHOR]

Mixed ionic-electronic xLi2O-(1-x)[0.25Bi2O3-0.35ZnO-0.30P2O5] (x = 0.05, 0.15, 0.25, 0.35, and 0.45) glasses have been formed by melt-quenching procedure to examine their physical, thermal, and dielectric characteristics. The physical investigation exposed that the density decreases from 5.23 to 4.74 g·cm−3 with the addition of Li-ions into the glassy matrix. Thermal investigations have been carried out using DSC technique. The values of Glass transition temperature (368.21–301.65) °C, and peak crystallization temperature (561.61–511.21) °C are observed to decrease with the addition of Li2O content. Conductivity spectra of as-prepared samples have been studied in frequencies ranging from 20 Hz to 2 MHz temperature range of 373–513 K. It becomes apparent that when the temperature rises, the dielectric loss and dielectric constant of the systems under study decrease. The quantities of dielectric loss and dielectric constant are projected to escalate with increasing temperature while diminishing with higher frequencies. The Kohlrausch–Williams–Watts model is employed to analyze the relaxation process in glass samples. This model demonstrates that the charge carriers adhere to non-Debye-type relaxation. Some thermodynamic parameters linked with the dielectric relaxation process have also been investigated. Impedance spectroscopy analysis suggests that electric conduction arises via Li and electrons/polarons, which makes the studied materials appropriate for energy storage applications. [ABSTRACT FROM AUTHOR]

Currently, there is growing interest in Ag 2 O doping in oxide glasses through optimal selection of excitation wavelengths to achieve efficient luminescence via either up or down-conversion processes. In this present work, we report the influence of Ag nanoparticles/aggregates on the structural and spectroscopic characteristics of melt-quenched Ag 2 O - co-doped (19.5-x)Li 2 O+70B 2 O 3 +10CaO+0.5Nd 2 O 3 +xAg 2 O glasses. Systematic studies were conducted using XRD, Raman spectroscopy, HR-TEM, MAS-NMR, UV–Visible–NIR, Photoluminescence, and decay kinetics techniques. The XRD analysis conclusively indicates the absence of crystalline peaks. However, HR-TEM analysis showed a reduction in the size of AgNPs from 14 nm to 11 nm with an increase of Ag 2 O concentration from 0.25 mol% to 0.5 mol%, respectively. The RAMAN and MAS-NMR (11B and 7Li) revealed the modification in the local structure induced by the Ag 2 O as revealed by the predominant borate structural units, and silver (Ag) acted as a modifier in the glass matrix. The absorption spectra of all samples exhibit a characteristic peak of Nd3+ ions. Interestingly, the LCBNd0.5Ag0.5 glass sample exhibits the SPR peak at 416 nm, indicating that the lower limit of Ag 2 O in LCBNd0.5 is <0.5 mol%. Luminescence studies at different excitation wavelengths (350, 525, and 584 nm) reveal the predominant emission at 877 nm and 1058 nm, whose emission intensity increased with Ag 2 O concentration. Samples with Ag 2 O-doped LCBNd glasses exhibit identical lifetime values, indicating the absence of luminescence-quenching and the presence of Ag aggregates leading to the SPR effect. Based on our findings, the LCBNd0.5Ag0.5 sample demonstrated superior performance to other samples, with the highest emission under an excitation of 350 nm. [ABSTRACT FROM AUTHOR]

A series of novel Sn2+ doped boroaluminate glasses were prepared by the traditional melt quenching method in this work. Their glass network structure, luminescent properties, and mechanisms were studied in detail. The main framework of the glass network was dependent on the glass network former (B 2 O 3) and intermediate (Al 2 O 3), and was characterized by the 11B and 27Al NMR spectra. Broadband tunable blue-violet emissions ranging from 320 to 550 nm were realized by regulating the glass network structure through optical basicity. The quantitative relationship between optical basicity and emission/excitation peak positions and intensities, FWHM, and Stokes-Shift of this Sn2+-doped glass were revealed, according to which the luminescent properties of Sn2+ could be modulated and even predicted in the future. This work will enrich our understanding of the luminescent properties of Sn2+ ions and the variations of glass network structure, guiding the design of efficient and tunable luminescent boroaluminate glass. [ABSTRACT FROM AUTHOR]

Cerium (Ce) ions exhibit multifunctional biological properties, such as anti-inflammatory, antioxidant, antimicrobial, and anticancer properties. Consequently, the development of Ce-containing biomaterials with therapeutic characteristics has received considerable research attention. In this study, Ce-doped 13–93 bioactive glass (Ce-BG) was prepared using the conventional melt-quenching method. The physical phases, surface morphologies, elemental contents, and elemental valence states of the samples were analysed. The concentration of the ions released from the samples in deionised water was determined, and their ability to induce hydroxyapatite was evaluated. The photothermal properties were tested by irradiating the samples with an 808 nm laser. The results indicate that an increase in the Ce content within a certain range did not affect the amorphous structure and morphology of the bioactive glass. Ce content variation affected the photothermal effect of Ce-BG. The wet state powder sample could be rapidly heated up to 58.24 °C under 2 W/cm2 laser irradiation at 5 mol% Ce doping, showing the best photothermal performance. Further, bacterial experiments demonstrated the good antimicrobial effect of this sample. Simulated body fluid immersion experiments revealed the ability of the Ce-BG to induce hydroxyapatite production. Furthermore, in vitro cell culture studies showed that the Ce-BG was not toxic to MC3T3-E1 cells and induced cell proliferation after 3 days. Therefore, Ce-BG is a promising bioactive material because of its favourable photothermal effects, antimicrobial properties, and biocompatibility. [ABSTRACT FROM AUTHOR]

The large size (4 cm × 4 cm × 1 cm) Ce3+-doped high gadolinium oxyfluoride glass with density of 5.83 g/cm³ was prepared by the melt quench method at 1220 °C. The glass is colorless and transparent over the visible range. The prolonged decay time under 275 nm UV light demonstrates the energy transfer from Gd3+ ions to Ce3+ ions. The X-ray excited luminescence spectra (XEL) show the emission peak corresponds to the 5d→4f transitions of Ce3+ ion. The integral emission intensity of glass was compared with that of bismuth germanate oxide (BGO) crystals. The scintillation property of glass was studied under the γ -ray from 137Cs source and a clear energy peak was observed with light yield (LY) over 1100 ph/MeV. The scintillation decay time comprises fast and slow components. All results presented in this work indicate the appropriate potential to be high-energy rays detecting material for CEPC. [ABSTRACT FROM AUTHOR]

Lithium-zinc-germanate glass-ceramics doped with Mn ions are synthesized by volume crystallization method. Structural studies show nucleation of different forms of lithium germanate crystals depending on the isothermal treatment regime of the initial glass. With the increase of the heat treatment temperature and the lithium content in the initial glass, the [GeO 4 ] /[GeO 6 ] ratio in the nucleated crystalline phases increases. The initial distribution of Mn2+/Mn3+/Mn4+ is defined by the Li 2 O/ZnO ratio in the glass composition: the ratio growth increases the contribution of Mn4+ over the Mn2+ and Mn3+. Low-temperature heat treatment of initial glass leads to uprise of intense red emission of Mn4+ ions in the octahedral environment. High-temperature heat treatment leads to occurrence of intense green emission related to Mn2+ ions in a tetrahedral environment. Discussions on all transformations of symmetry, the crystal field strength of Mn ions' environment and their valence state based on the results of optical spectroscopy, ESR and XRF studies are provided. The maximum quantum yield of red luminescence is 61%, and of green luminescence is 23%. The synthesized glass-ceramics can be used as a luminescent converter of the UV LED radiation with the maximum energy efficiency of 20%. [Display omitted] [ABSTRACT FROM AUTHOR]

Quantitative composition‐structure‐property (C–S–P) relationship analysis is a promising approach to correlate structural features with properties of glasses that have complex structures and lack long‐range order. In this study, the structure and spectroscopic properties of two typical P2O5‐MO‐K2O‐Al2O3 (M = Mg, Ba) quaternary phosphate laser glasses doped with Nd3+ ions are calculated and predicted. By using the nearest‐neighboring congruently melting compounds in the phase diagram as "component and structural motifs", correlations with properties and insights on glass behaviors can be obtained. Two key physical properties and five spectroscopic properties are predicted and verified with an error of less than 5% and 10%, respectively. Furthermore, two C–S–P databases with more than 1000 glass compositions are established for designing and optimizing new laser glasses. The results show that this approach not only gets rid of the traditional qualitative research method which relies on empirical formulas, but also promotes the quantitative calculation and predictable design of glass research. [ABSTRACT FROM AUTHOR]

Two series of samarium doped lead-tellurite glass embedded with titanium nanoparticles (Ti NPs) of different compositions (60 − x)TeO2-30PbO-10ZnO-xSm2O3 (x = 0.5, 1, 1.5, 2, 2.5 mol%) and (58.5 − x)TeO2-30PbO-10ZnO-1.5Sm2O3-xTiO2 (x = 0.3, 0.6, 0.9, 1.2, 1.5 mol%) were prepared using conventional melt quenching technique. The existence of a broad hump XRD pattern verifies the amorphous nature of glasses. The homogeneous distribution and growth of spherical and non-spherical TiO2 NPs (average diameter ~ 11.11 ± 0.13 nm) in the glassy matrix are evidenced from the TEM analyses. The HRTEM confirmed the presence of TiO2 NPs by measuring the lattice spacing of TiO2 NPs, which is found to be 0.211 nm. The UV–Vis-NIR absorption spectra reveal nine bands corresponding to the transition from ground state 6H5/2 to excited states 4I13/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2, and 6F1/2; the most intense hypersensitive bands are F9/2,6F7/2,6F5/2, and 6F3/2. The down-conversion corresponding to Sm3+ ions transitions under 404-nm excitation reveals four emission bands centered at 548 nm, 583 nm, 628 nm, and 692 nm related to the transitions 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, 4G5/2 → 6H9/2, and 4G5/2 → 6H11/2, respectively. The highest transition band relative intensity to the other transition bands is 4G5/2 → 6H7/2, and the intensity of 4G5/2 → 6H11/2 is the lowest. Additionally, the glass sample TPZST3 with 0.9 mol% of TiO2 NPs possesses the greatest WCA of 105.24° which means that the TPZST3 has a hydrophobic nature; this suggests that TPZST3 can be a good candidate for developing self-cleaning glasses applications. [ABSTRACT FROM AUTHOR]

Trivalent erbium ions doped (48 – x) AlPO4 + 15K2O + 12MgF + 20Na2O + 5NaF + xEr2O3 glass samples have been prepared utilizing the melt-quench process and studied to understand the efficacy of Er3+ ions content on physical, structural and luminescence attributes of host glass. The functional groups of the glass structure such as metaphosphate, orthophosphate and pyrophosphate have been elucidated through Fourier Transform Infrared (FTIR) spectroscopic investigation. The least-square approach was used to calculate the Judd–Ofelt parameter from the oscillator strength of the Er3+ ion transitions. The luminescence emission data captured in the visible and near-infrared (NIR) province using 380 and 980 nm excitation wavelengths. The up-conversion (recorded at the excitation at 980 nm) of 0.5 Er glass exhibited emission at 664, 550 and 488 nm wavelengths. The decay plots of the studied glass specimens were measured at 980 nm excitation. The McCumber (MC) theory has been implemented to calculate the gain coefficient of the 0.5 Er glass and flat gain curve was drawn for S-band, C-band and L-band. The attributes for optical amplification were ascertained, including the quality factor (0.85), branching ratio (1), stimulated emission cross-section (1.3 × 10–20 cm2), gain bandwidth (1.26 × 10–25 cm3) and optical gain (0.394 × 10–23 cm2 s) for 0.5 Er glass. The yellowish green light emission ability of the 0.5 Er glass after 980 nm excitation evident through CIE co-ordinates position (x 0.36, y 0.58) at 1931 CIE chromaticity diagram. The spectroscopic and luminescence results endorse that the alumino–phosphate glass specimens loaded with 0.5 mol% of Er2O3 are beneficial for NIR and green light emission applications. [ABSTRACT FROM AUTHOR]

Abstract: Newly cerium oxide (CeO2)-doped borophosphate glasses with chemical formula B2O3 + P2O5 + CaO + Na2O + xCeO2: x = 0.0–1.5 mol% were fabricated by using the conventional melt-quenching technique. Structural, optical, and physical characteristics of the proposed samples have been investigated. XRD measurements proved the amorphous nature of the prepared BCe-X glasses. Density (ρ) of samples varied from 2.83 ± 0.01 g/cm3 to 2.95 ± 0.01 g/cm3, while the molar volume (Vm) reduced from 28.41 ± 0.01 cm3/mol to 27.81 ± 0.01 cm3/mol as CeO2 increased from 0.0 to 1.5 mol% in the BCe-X network. The absorption spectra of the proposed BCe-X glasses showed the absence of the absorption bands at 345 and 450 nm. The values of refractive index (n) decreased during the wavelength range (normal dispersion) for the present BCe-X glass samples. Values of optical band gap (Eg) exhibited a reduction behavior, it found be decreased from 4.04 eV to 3.89 eV as the CeO2 concentrations elevated from 0 to 1.5 mol %. The non-linear refractive index (n2) and the third-order non-linear optical susceptibility (χ(3)) increased gradually with CeO2 additives. Results showed that the suggested BCe-X compositions can be applied for many advanced opto-electronic and communication systems. [ABSTRACT FROM AUTHOR]

Silica-aluminum borates (SiO 2 -R 2 O 3 -R 2 O-RO-ZrO 2 system) with La 2 O 3 replacing BaO were preparing using the conventional melt quenching process. The impact of substituting BaO with La 2 O 3 on the glass structure was examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Raman. The density, thermal properties, alkali resistance and dielectric properties of the glasses were measured and compared using Archimedes, Differential Scanning Circuit (DSC), Thermal Expansion Calorimetry (TEC), Weight Reduction and Impedance Spectroscopy. The viscosity of the glass system was calculated from the thermal properties and discussed in comparison with the wetting angle at 1000 °C. The results showed that the glass does not undergo precipitation. With the increase of La 2 O 3 to BaO substitution, the Q4 in the glass network structure transforms to Q0+Q1 and Q2, causing depolymeriation of the glass structure. This results in an increase in the density of the glass, as well as an increase and subsequent decrease in the thermal expansion coefficient. Additionally, the glass transition temperature and glass softening temperature decrease and then increase, which was due to the high field strength of La3+. When substituting 5 wt% of BaO with La 2 O 3 , The glass displayed the lowest dielectric constant and dielectric loss, along with the best alkali resistance. Viscosity calculations showed that the viscosity gradually increases at 1000 °C with the increase of La 2 O 3 substitution, which was consistent with the wettability results. The glass components in the 0-5 wt% weight range all satisfy the iron-sealed glass wetting angle requirements. [ABSTRACT FROM AUTHOR]

In this work, glass samples were obtained by melt-quenching in the binary system (100-x)KPO 3 -xNb 2 O 5 with x = 20, 30, 40, and 50 mol%. Thermal properties investigated by DSC together with structural investigations by Raman spectroscopy allowed to understand the structural effect of Nb 2 O 5 incorporation in the potassium phosphate glass network. A transparent glass-ceramic has also been produced by heat treatment of the 50KPO 3 –50Nb 2 O 5 glass sample. Density, molar volume, atomic packing, and refractive index were determined and increased with Nb 2 O 5 content. Chemical resistance in several corrosive aqueous solutions was found to increase with Nb 2 O 5 content and crystallization. Vickers hardness as well as elastic modulus and hardness obtained from nanoindentation experiments also strongly increased with higher niobium contents, indicating that not only optical properties but also chemical and mechanical properties are improved with niobium incorporation in the phosphate glass network. [ABSTRACT FROM AUTHOR]

Ceramic polyolefin composites have the capability to transform into hard ceramics when exposed to fire conditions. During the ceramization process, the formation of new crystalline phase plays a crucial role in enhancing flame‐retardant and ceramifiable properties. Consequently, ceramic polyolefin composites show great potential for the applications in fire‐resistant wires and cables. In this article, the incorporation of the compound flame retardant consisting of ammonium polyphosphate/melamine cyanurate/zinc borate (APP/MCA/ZB) was found to enhance the flame retardancy and ceramization of polyethylene/wollastonite fiber/phosphate glass frits (PE/WF/PGF) composites. The results indicated that ceramifiable flame‐retarding PE composites with compound flame retardant exhibited superior flame retardancy compared to pure PE and PE composites with a single flame retardant. Specifically, the limiting oxygen index (LOI) was significantly increased to 26.8%, and the vertical combustion test rating in UL‐94 (test for flammability of plastic materials for parts in devices and appliances) reached V‐0. During the heating process, ZB thermally decomposed to produce 2ZnO ⋅ 3B2O3, which reacted with CaSiO3 to form a silicate glass intermediate phase (CaO ⋅ SiO2 ⋅ 2ZnO ⋅ 3B2O3). APP thermally decomposed to produce (HPO3)n, which reacted with 2ZnO ⋅ 3B2O3 to form a phosphate glass intermediate phase (nP2O5 ⋅ 2ZnO ⋅ 3B2O3). These two glass phases experienced a eutectic reaction with WF, ultimately producing the formation of a new crystalline phase of calcium zinc phosphate (CZP, Ca19Zn2(PO4)14). This newly formed CZP phase made sintered ceramics more compact and had higher flexural strength. The flexural strength of ceramic residues after sintering was 11.68 MPa, meeting the requirements for practical applications. [ABSTRACT FROM AUTHOR]

Glass microspheres have gained significant attention over the years in the field of photonics due to their application in whispering gallery mode (WGM) microresonator platforms. However, the synthesis of glass spheres in the micro regime remains challenging, while it relies mostly on complicated synthetic methods or sol–gel chemistry. Herein, we demonstrate the controlled formation of phosphate glass microspheres by means of a simple, fast, low-temperature, post-glass melting thermal treatment of previously quenched glass. Moreover, we report on the simultaneous formation of silver nanoparticles (AgNPs) on the surface of glass spheres upon the same treatment. The formation of metal nanoparticles onto the glass spheres induces attractive optical and plasmonic properties, believed to be suitable for WGM resonator-based applications, as well as a wide range of optoelectronic, photonic, and sensing applications. [ABSTRACT FROM AUTHOR]

The influence of various trivalent lanthanides was investigated in the silica phosphate multi-component glass matrix, synthesized by the sol-gel method. The prepared glasses were analyzed to explore the degree of bandwidth amplification for telecommunication systems, and the potentiality of lasing media and smart glass films. Alkaline earth metal ions of Ca2+ were effectuated as a glass modifier, mediating the formation of non-bridging oxygen with the glass formers, and imputing favorable structural attributes to the glasses for versatile applications. The bonding parameter derived from the average nephelauxetic ratio implies covalency around the rare earth ion sites in the Er3+ and Nd3+ doped systems, while the Sm3+ doped glass exhibits ionicity. In the silica-based glass matrix singly doped with Yb3+, the coexistence of Yb3+/Yb2+ ions was evidenced. Transitions across 4f14 and 4f135d levels of Yb2+, with an experimental lifetime of 45.8 ns would provide prospective pulsed yellow lasers, for non-invasive therapeutics. Er3+ doped glass evinced a large bandwidth of 93.775 nm at 1477 nm and a high quantum efficiency of 97%, favorable for O + E + S-band telecommunication networks. The transition corresponding to 4 G 5 / 2 → 6 H 7 / 2 of Sm3+ and 2 G 7 / 2 → 4 I 9 / 2 of Nd3+ is suggestive that the respective doped glasses could be devised into solid-state red and green laser sources. Novel near-infrared emission at 1476 nm was also evidenced in the Sm3+ and Nd3+ doped systems. Prominent absorption at 280 nm and complete transparency in the visible region observed in the Ce3+ mono-doped system make it ideal for smart glasses as UVB and UVC shielding films. [ABSTRACT FROM AUTHOR]

In this work, a novel series of borophosphate glasses of the system 40B 2 O 3 –25P 2 O 5 –(20-x)Na 2 O–15CaF 2 –xMgO (x = 0, 2.5, 5, 7.5, and 10 mol%) were synthesized using the melt-quenching technique. The effect of replacing Na 2 O with MgO in the glasses was analyzed by the physical and bioactive properties. The glasses were characterized by density, molar volume, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Differential thermal analysis (DTA), bioactivity tests in simulated body fluid (SBF), pH measurements, mass loss, and verification of cellular compatibility in RAW 247 murine macrophages. XRD and FTIR analyses were performed before and after immersion in SBF to verify the bioactivity. Density, molar volume and FTIR results before SBF showed structural changes in the glasses due to the addition of MgO. The pH and mass loss measurements allowed to verify the degradation behavior of the glass series as a function of MgO concentration. The DTA data showed an increase in T g , T x, and thermal stability due to the increase in MgO addition. XRD and FTIR analyses after SBF soaking showed superficial formation of apatites and other calcium phosphates of biological interest in the samples, attesting the bioactivity. Cytotoxicity assessed by MTT assay on the cell line RAW 247 showed that at a concentration of 500 μg/mL all glasses were compatible (non-cytotoxic). The results suggest that the synthesized glasses are bioactive, with the sample containing 5 mol% MgO exhibiting the bioactivity and biocompatibility required for biomaterial applications. [ABSTRACT FROM AUTHOR]

Based on calculations, the spatial distribution of the local electric field (LEF) for various structural configurations of silver nanoparticles (NPs) in silicate and zinc-phosphate glasses was studied. The features of this distribution determine the efficiency of energy transfer from plasmonic NPs to rare earth (RE) ions located in the particle vicinity. The mechanism of energy transfer through field enhancement via surface plasmon resonance of particles, which is dominant for NPs of sizes of ≥ 5 nm, is determined by several factors. To clarify their roles and significance, the dependencies of LEF upon the size, spatial distribution, and degree of agglomeration of silver NPs in glass were studied. Comparative analysis of the nature of the field enhancement in places of hypothetical location of RE ions was carried out on the basis of a visual representation of the spatial distribution of the LEF in the vicinity of agglomerates of plasmonic NPs. Based on simulations, the dependencies of LEF intensity enhancement, the spatial distribution of such places in relation to the nearest plasmonic particle, upon the concentration of NPs, their size, degree of agglomeration, and the presence of small (≤ 5 nm) particles in the sample along with the relatively large ones, were determined. The optimal configuration of silver particles in glass for obtaining the maximum average enhancement of LEF intensity per the site of possible location of RE ion is revealed to be an agglomerate of NPs with sizes slightly larger than 25 nm and average distances between particle centers about 30 nm. [ABSTRACT FROM AUTHOR]

The luminescent properties of erbium(III)-doped fluorozirconate glass and fluorozirconate phosphate glass and glass ceramics containing NaPO3 were compared. The glasses were obtained by rapid melt quenching and were characterized using luminescence spectroscopy, differential thermal analysis, x-ray diffraction, and transmission electron microscopy. When NaPO3 was added, the relative luminescence intensity of Er(III) in the near infrared (NIR) region doubled at 1530 nm (4I13/2 → 4I15/2 transition). The luminescence intensity of other bands in the visible and NIR regions decreased. Luminescence quantum yields and lifetimes of the studied samples were measured. The reasons for the change in luminescence intensity after addition of NaPO3 and heat treatment of the samples were discussed. [ABSTRACT FROM AUTHOR]

Europium (Eu) ion–doped luminescent materials have attracted considerable attention for their numerous optical applications. Eu‐doped Ca–Al–Si–O(–N) glasses were synthesized from a mixture of oxynitride glasses and Eu2O3 powder using a standard melt‐quenching technique in a radiofrequency furnace. The source Eu trivalent ions primarily changed to Eu2+ during melting, and the ratio of Eu2+ ions increased with an increase in Eu content in the starting mixture. All the prepared glasses exhibited photoluminescence (PL) owing to the 5d–4f transition of Eu2+ ions. The absorption edge and PL wavelength shifted to longer wavelength with an increase in Eu content. Moreover, oxynitride glasses exhibited a longer wavelength than those of oxide glasses. The internal quantum efficiency (IQE) increased with the increase in Eu content until it reached a maximum. X‐ray absorption structure and electron spin resonance spectroscopies were used to determine the local structure of Eu ions, which confirmed that changes in the local structure of Eu ions were responsible for the shift in PL peak and the change in IQE. The development of the Eu‐doped Ca–Al–Si–O–N glasses is highly inspiring for transparent phosphors. [ABSTRACT FROM AUTHOR]