Non-bridging Oxygen Research Articles

Evolution of point defects in mechanical cracks of fused silica after CO2 laser melting

The traditional polishing method inevitably results in subsurface cracks in the fused silica, which seriously degrades their ultraviolet laser damage resistance. CO2 laser irradiation can melt these cracks and improve their laser induced damage threshold (LIDT). Photoluminescence spectrum and SEM-FIB were employed to investigate the changes in the material microstructure at the crack location with CO2 laser melting. The density of the oxygen-deficient centers of type II (ODC II) defects decreases, while the density of the non-bridging oxygen hole center (NBOHC) defects increases after high-temperature melting. The reason for this change is related to the dihydroxylation reaction and the participation of environmental oxygen in the defect type conversion. The reduction of ODC II defects is most likely the reason for the improvement of LIDT.

Impact of TiO2/B2O3 ratio on the structure and optical properties of Na2O–CoCl2–TiO2–B2O3 glass

In this study, borate glass doped with constant cobalt chloride (CoCl2) content and different ratios of TiO2/B2O3 were prepared using the melt-quenching technique. The influence of the TiO2/B2O3 ratio on structure, optical, magnetic, electronic transitions, and linear and nonlinear optical features was studied. Structurally, XRD confirmed the amorphous structure, while EDX confirmed the incorporation of titanium cation. Meanwhile, the density increases, and the molar volume reduces with further ratios of TiO2/B2O3 to the glass matrix. Also, FTIR spectra confirmed the decreased presence of non-bridging oxygens (NBO), and different structural units such as BO3 and BO4. Optical studies showed the formation of absorption bands at about 301–327 nm, 375 nm, and 434 nm with TiO2/B2O3 ratios. Deconvolution procedures are necessary to detach the three electronic transitions and the glass absorption edge. The three electronic transitions can be explained in terms of titanium cations (Ti) oxidation states where Ti3+ cations display absorption bands in the wavelength range 440–480 nm. In contrast, Ti4+ cations display no absorption bands in the visible range but only show ultraviolet absorption bands. According to the electronic transition associated with Co cations are; the band at ∼497–500 nm is associated with 4T1g (F) → 2T1g (H) octahedral electronic transitions of Co2+ cations, while the band positioned at 577–578 nm is associated with 4A2 (4F)→4T1(4P) tetrahedral electronic transitions of Co2+ cations. The band is positioned at 648–650 nm and is associated with 5T2g→ 5Eg octahedral electronic transitions of Co3+ cations. On the other hand, with increasing TiO2/B2O3 ratio, optical band gaps decrease from 3.51 eV to 3.15 eV, and the samples color transformed from light blue to dark blue. Furthermore, the addition of TiO2/B2O3 ratio increases the linear and nonlinear refractive indices. ESR data indicate that Co2+ ions exist in both octahedral sites, with g ⁓ 4.10, and tetrahedral sites, with g ⁓ 2.40. Finally, we concluded the significant influence of the TiO2/B2O3 ratio on the structure, optical and magnetic properties, and linear and nonlinear optical parameters of cobalt borate glass. These results recommend the present glass samples for future applications in various photonic devices within the visible range.

Influence of the Addition of Zinc, Strontium, or Magnesium Oxides to the Bioglass 45S5 Network on Electrical Behavior.

45S5 Bioglass has been widely used in regenerative medicine due to its ability to dissolve when inserted into the body. Its typically amorphous structure allows for an ideal dissolution rate for the formation of the hydroxyapatite layer, which is important for the development of new bone. This bioactive capacity can also be controlled by adding other oxides (e.g., SrO, ZnO, and MgO) to the 45S5 Bioglass network or by storing electrical charge. Ions such as zinc, magnesium, and strontium allow for specific biological responses to be added, such as antibacterial action and the ability to increase the rate of osteoblast proliferation. The charge storage capacity allows for a higher rate of bioactivity to be achieved, allowing for faster attachment to the host bone, decreasing the patient's recovery time. Therefore, it is necessary to understand the variation in the structure of the bioglass with regard to the amount of non-bridging oxygens (NBOs), which is important for the bioactivity rate not to be compromised, and also its influence on the electrical behavior relevant to its potential as electrical charge storage. Thus, several bioactive glass compositions were synthesized based on the 45S5 Bioglass formulation with the addition of various concentrations (0.25, 0.5, 1, and 2, mol%) of zinc, strontium, or magnesium oxides. The influence of the insertion of these oxides on the network was evaluated by studying the amount of NBOs using Raman spectroscopy and their implication on the electrical behavior. Electrical characterization was performed in ac (alternating current) and dc (direct current) regimes.

Atomistic mechanism of structural and volume relaxation below glass transition temperature in a soda-lime silicate glass revealed by Raman spectroscopy and its DFT calculations.

To elucidate the atomistic origin of volume relaxation in soda-lime silicate glass annealed below the glass transition temperature (Tg), the experimental and calculated Raman spectra were compared. By decomposing the calculated Raman spectra into specific groups of atoms, the Raman peaks at 800, 950, 1050, 1100, and 1150cm-1 were attributed to oxygen and silicon in Si-O-Si, non-bridging oxygen in the Q2 unit, bridging oxygen in low-angle Si-O-Si, non-bridging oxygen in the Q4 unit, and bridging oxygen in high-angle Si-O-Si, respectively. Based on these attributions, we found that by decreasing the fictive temperature by annealing below Tg - 70K, a homogenization reaction Q2 + Q4 → 2Q3 and an increase in average Si-O-Si angle occurred simultaneously. By molecular dynamics simulation, we clarified how the experimentally demonstrated increase in average Si-O-Si angle contributes to volume shrinkage; increasing Si-O-Si angles can expand the space inside the rings, and Na can be inserted into the ring center.

Effect of BaO/Al2O3 molar ratio on the viscosity and structure of CaO[sbnd]SiO2[sbnd]MgO[sbnd]Al2O3[sbnd]BaO slag

In this study, the effect of BaO/Al2O3 molar ratio on the viscosity and structure of CaOSiO2MgOAl2O3BaO slag was investigated. The results revealed that the viscosity first increased and then decreased with increasing the BaO/Al2O3 ratio, and the transition point occurred at the ratio of 0.36. Deconvolution of Raman spectra showed that the Q3 unit first increased and then decreased with increasing the BaO/Al2O3 ratio, while the Q0, Q1 and Q2 units presented the opposite trend. FTIR and XPS analyses indicated that the [SiO4] and [AlO4] tetrahedra polymerized due to the charge compensation of Al3+ by Ba2+ and the increase in bridging oxygen prior to increasing the BaO/Al2O3 ratio to 0.36. However, once the BaO/Al2O3 ratio further increased, the tetrahedra gradually depolymerized owing to the interrupting effect of BaO and the increase in non-bridging oxygen. Spectral analysis demonstrated that the degree of polymerization of slag was the main factor affecting viscosity.

Structural investigation and thermal properties of Al2O3-PbO-B2O3 glasses

Two series of aluminum lead borate glasses, (Al2O3)y(PbO)35-y(B2O3)65 and (Al2O3)y(PbO)70-y(B2O3)30, were prepared and effect of PbO → Al2O3 substitution on their structure and thermal properties was studied. The semi-quantitative analysis of the Raman spectroscopy data was used to structural interpretation of glass transition behavior in the Al2O3-doped lead borate glasses. The mechanisms of structural reorganization of glassy network under PbO → Al2O3 substitution were found to differ for the studied series although Al3+ ions are incorporated in the glass network, mainly, in form of AlO4 units in the both cases. The formation of AlO4 tetrahedra is accompanied by transformation of various isolated borate anions into finite-sized metaborate chains as well as the conversion of four-fold coordinated [BØ3O−]− species with one non-bridging oxygen atom into fully polymerized [BØ4]− tetrahedra in the (Al2O3)y(PbO)70-y(B2O3)30 glasses. In the series of glasses with high concentration of B2O3, B[4] → B[3] transformation including the shift of [BØ4]− ↔ BØ2O− equilibrium toward the right side is the main process of structural reorganization caused by PbO → Al2O3 substitution. In this case, the change in the network connectivity is determined by competition between increasing the amount of Al-O-B bonds against the background of decreasing the amount of B-O-B bonds between borate structural species. In the B-poor series, the glass transition temperature increased with Al2O3 from 280 to 360 °C, and the crystallization peak onset occurs at 340 and 380 °C for the glasses with the 0 and 3 mol.% Al2O3 contents, respectively (higher aluminum oxide contents already prevent crystallization). In the B-rich series, Tg increases with the Al2O3 content from 430 to 490 °C, and the crystallization occurs at 560 °C only for the Al2O3-free glass. The structural relaxation behavior in the glass transition rage was described in terms of the Tool-Narayanaswamy-Moynihan model. The activation energy for the relaxation movements was found to be non-monotonous in case of both compositional series.

Synthesis, optical and magnetic properties of Nd2O3/borate strontium fluoride glasses

The present work conducts the synthesis, thermal, optical, and magnetic characterization of (60-x)B2O3+20Li2O+20SrF2+ x Nd2O3 where x = 0, 0.5, 1, 1.5, 2 mol% glass samples. The samples were investigated via X-ray diffraction (XRD), Raman spectroscopy, differential scanning calorimetry (DSC), UV–Vis absorption spectroscopy, and vibrating sample magnetometry (VSM). XRD patterns for borate strontium fluoride glass samples doped with Nd2O3 showed broad humps around 30 and 43°, indicating their amorphous structure. Raman spectra of glass samples indicated that as Nd3+ ions were added to the host matrix, there was an increase in Raman intensity due to bond breakdown and the development of more non-bridging oxygen (NBO) species. The DSC data of the borate strontium fluoride glass samples doped with Nd2O3 demonstrated that the glass transition temperature (Tg) generally increased. UV–Vis absorption spectra showed transitions in Nd3+ ions doped borate glasses that are associated with the bands at different wavelengths, attributed to 4G5/2+2G7/2, 2H11/2, 4F9/2, 2H9/2 +4F5/2, and 4F3/2. The refractive index of borate strontium fluoride glass samples doped with Nd2O3 increased. The saturation magnetization values decreased from 0.9 to 0.29 upon increasing the Nd2O3 percentage (0–2 mol%). These low saturation magnetization glass samples can be used in spintronic devices to effectively reduce switching current density and lower the damping constant.

Deciphering the structure and potassium-ion transport mechanism of potassium borate glass.

Potassium borate glass has great potential as an ion transport material. The ion transport rate is closely related to the microstructure of the glass. However, the disorder and variations in boron and oxygen atom types in the glass structure pose challenges in the analysis of this complex glass structure. In this work, the structure of potassium borate glass was unveiled through the neutron diffraction method and ab initio molecular dynamics (AIMD) simulations. The B-O, K-O, and O-O atomic interactions, bond lengths, coordination numbers, cavity distribution, ring structure distributions and other detailed information in the microstructure of potassium borate glass were obtained. By comparing the structure and properties of potassium borate glass with those of crystals of similar components, it is found that the bond lengths of 3B-BO (BO, bridging oxygen), 4B-BO and 3B-NBO (NBO, non-bridging oxygen) are longer than those of corresponding crystals, so the structure of the boron-oxygen network is looser and the density is smaller than that of similar crystals. Moreover, we found a rule that in both borate glass and crystal, the increase of NBO shortened the length of the B-O bond, and the increase of 4B increased the length of the B-O bond. The key structures affecting the transport rate of K+ were NBO, chain structure units and cavities. This work will provide reference data for designing and developing electrically conductive amorphous materials with faster potassium-ion transport rates.

Radiation modification of quartz and its spectral characteristics

The nature of the structural phase transition of quartz under neutron irradiation was studied by X-ray diffraction analysis. The kinetics of gamma luminescence (GL) bands in quartz crystals grown on seeds irradiated with neutrons with a dose of 5-1018..1019 and 5-1019 n/sm2 after additional neutron irradiation of 1016- 8.1020 n/sm2 in the temperature range 77-300 K. Based on experimental data, it is shown that all the structural characteristics of the seed are transferred to the grown crystal. This opens up the possibility of obtaining quartz crystals with predetermined properties. Diffraction parameters of quartz irradiated with neutrons and grown on neutron-irradiated seeds (n/sm2). Based on the results of studies of GL, the redistribution of the intensities of photoluminescence bands under illumination (λw = 300-340 nm) without heating and with heating in the temperature range 300-720 K, the dependence of the intensities of luminescence bands on the neutron fluence, it was assumed that the luminescence centers are at 550 and 660 nm are, respectively, peroxide radicals and non-bridging oxygen atoms located at the interfaces between the α- and β-phases of quartz.

Copper nanoparticle and point defect formation in Cu+-Na+ ion-exchanged glass using protons of 2 MeV energy.

There are several applications for irradiating materials with protons that could provide alternative methodologies to synthesize and induce the formation of new compounds of different size scales. In this study, we explored the effects of proton irradiation oncommercial glass silicate that was previously subjected to a Cu+-Na+ ion exchange (IE) treatment at 600 °C for a duration of 60 min. The ion-exchanged glass samples were irradiated with protons (p+) of 2 MeV energy at doses in the range of thousands of grays (3.3 × 103, 7.9 × 103 Gy) and hundreds of thousands of grays (3.6 × 105 Gy). Significant changes in the optical and structural properties were observed post the radiation treatment. The UV-Visible absorption spectra of the irradiated samples revealed the appearance of overlapping absorption bands, which could be deconvoluted into three Gaussian-shaped bands peaking at 566, 620 and 680 nm. These three bands could be attributed to the surface plasmon resonance (SPR) of copper nanoparticles, non-bridging oxygen hole centers (NBOHCs) and self-trapped hole (STH) defects, respectively. Prominent photoluminescence (PL) was observed in the Cu-exchanged and irradiated samples, mainly induced by the presence of both Cu+ and Cu2O. Increasing the irradiation dose led to an increase in the PL intensity due to the conversion of Cu2+ ions into Cu+. This result was confirmed by electron paramagnetic resonance (EPR) spectroscopy that shows a decrease in the Cu2+ signal when increasing the dose of proton exposure. Transmission electron microscopy (TEM) and high-resolution TEM (TEM and HRTEM) observations confirmed the presence of copper nanoparticles (CuNPs) in the doped and p+ irradiated Cu-exchanged glass silicate samples. These CuNPs were found to be crystalline with an average size of 12.39 nm.

An investigation on 45S5 nanobioactive glass using FTIR and Raman spectroscopy

Bioactive materials are those that cause a number of interactions at the biomaterial-living tissue inter-face that result in the evolution of a mechanically strong association between them. For this reason, an implantable material’s bioactive behavior is highly advantageous. Silicate glasses are encouraged to be used as bioactive glasses due to their great biocompatibility and beneficial biological effects. The sol-gel method is the most effective for preparing silicate glasses because it increases the material’s bioactivity by creating pores. Glass densities are altered by the internal network connectivity between network formers and network modifiers. The increase in the composition of alkali or alkaline oxides reduces the number of bridging oxygens and increases the number of non-bridging oxygens by retaining the overall charge neutrality between the alkali or alkaline cation and oxygen anion. Higher drying temperatures increase pore densities, while the melt-quenching approach encourages the creation of higher density glasses. Band assignments for the BAG structure can be explained in detail using Fourier Transform Infrared (FTIR) and Raman spectroscopic investigations. Raman spectroscopy makes it simple to measure the concentration of the non-bridging oxygens in the silica matrix.

Structural Investigation and Optical Properties of Dysprosium (Dy3+) Ions Doped Oxyfluoro Antimony Borate Glasses for Photonics Applications.

Dysprosium oxide-doped glasses with a composition of 60B2O3-10Sb2O3-10Al2O3-10NaF-(10-x) LiF-xDy2O3 (x = 0.1,0.5, 1.0,1.5,2.0,2.5 mol%) were prepared using a conventional melt-quenching technique. The glasses were characterized through various analytical investigations, including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, refractive index, density, optical absorption, excitation, photoluminescence (PL) studies, decay measurements and radiation shielding parameters. The XRD and FT-IR confirms the glassy nature and functional groups present in the titled glass. The absorption spectra were used to determine the oscillator strength of the Dy3+ absorption transitions as well as the bond created with the O-2 ion in the titled glass network. The degree of the suitability of developed glasses for lasing applications was demonstrated by radiative parameters determined using Judd-Ofelt theory. In the prepared glass samples, the optical bandgap measurements indicate the presence of non-bridging oxygen (NBOs), localization of charges and donor centers in the titled glasses. Due to the de-excitation of 4F9/2 to the corresponding 6H15/2,6H13/2 and 6H11/2 states, the PL emission spectrum shows two main strong emissions at blue(480nm), yellow (575nm) and one less emission at red (663nm). The CIE coordinates determined using PL emission spectra reveal the coordinates that are falling within the white light region. Various shielding parameters such as mass attenuation coefficient, mean free path, effective atomic number were estimated to understand the radiative shielding nature of the titled glasses. Within the addition of Dy2O3, it was found that the shielding parameters values of the titled glass samples are increasing. The Mass Attenuation Coefficient, Half Value Layer and Mean Free Path of the as prepared glasses has been compared with different types of concretes to understand the shielding effectiveness of prepared glass.

Controlling photoluminescence of silicon quantum dots using pristine-nanostates formation

This study investigates the effective control of photoluminescence (PL) of silicon nanocrystals (Si–NCs) embedded in a SiO2 matrix, with a specific focus on tuning the luminescent wavelength profile and intensity for silicon-based optoelectronic applications. By manipulating the composition ratio (x) of SiOx, the well-known simultaneous changes in PL peak position and intensity were observed after annealing. To preserve the desired wavelength characteristics and enhance the luminesce intensity, we propose a novel approach to generate pristine nanostates (PNs) for Si-NC formation using proton irradiation (PI). The application of proton irradiation was found to be successful in significantly increasing PL intensity while strongly suppressing the peak position shifts. Through extensive spectroscopic analysis including PL, X-ray photoelectron spectroscopy, and absorption spectroscopy, we investigate specific defect states in the SiOx matrix, and identified as PNs. We interpret that these PNs consist of self-trapped exciton, E′ center, non-bridging oxygen hole center, and oxygen-deficiency center states. In the as-grown sample, the PNs promote appropriate phase separation and play a significant role in stabilizing the structure during the subsequent annealing processes. This study elucidates the Si-NC formation mechanism by enhancing O-diffusion-induced phase separation, a process accelerated in SiOx with controlled PNs. The proposed PI-induced PNs offer a novel pathway for developing Si-based optoelectronic devices with desired characteristics in the operating wavelength range. These findings open up promising possibilities for advanced silicon-based optoelectronic applications.

Achieving narrow bandwidth and high stimulated cross-section in Nd3+-doped LiCaB glasses for near infra-red laser amplifiers

The aim of this research is to examine the effects of Nd3+ ions on the spectroscopic characteristics of different concentrations of lithium-calcium-borate glasses and improve the emission cross section alongside bandwidth. The prepared glasses were produced with the melt-quenching technique and were thoroughly analyzed to determine their usefulness as laser amplifiers. Various studies were conducted, including X-ray diffraction (XRD), solid-state nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), absorption and emission measurements, and time decay curve measurements. The structural analysis using XRD and NMR techniques revealed that the glasses were amorphous and that non-bridging oxygen was present. Moreover, it was discovered that the glass-forming tendency and glass stability of these glasses improved with the concentration of Nd3+ ions. The glasses' absorption spectra display 10 transition states in UV and visible regions. Among all the prepared glasses, the lithium-calcium-borate glass doped with 0.5 mol % Nd3+ ions stand out with a stimulated emission cross-section value of 3.40 × 10−20 cm2 and a narrow bandwidth of 33 nm, making it an ideal lasing amplifier medium due to the 4F3/2 → 4I11/2 (1060 nm) transition. Theoretical Judd-Ofelt calculations were conducted to evaluate various parameters, including oscillatory strength, radiative parameters, radiative lifetime, gain bandwidth, figure-of-merit, and saturation current, for all transitions in the near-infrared region, to support the experimental investigations and offer a detailed discussion of these parameters.

Characterization of glass-ceramics developed from zinc leaching residue by sintering method

Zinc leaching residue is the waste residue produced by the wet zinc extraction process, which cannot be effectively utilized due to its complex composition and the presence of toxic heavy metals. At this stage, a large amount of residue is piled up in the tailing storage, there is a waste of resources and the risk of environmental pollution. This paper introduced a study on the preparation of glass-ceramic in building materials from zinc leaching residue by the sintering method, using silica sand and albite as additives. It was found that the glass-ceramics prepared with zinc leaching residue incorporation of 70–75 % and sintering temperature in the range of 900–1000 °C exhibited excellent mechanical properties and stable chemical properties. The zinc leaching residue content and the sintering temperature together controlled the crystallization process and influenced the properties of the glass-ceramic. Increasing the zinc leaching residue content caused an increase in the content of non-bridging oxygen bonds in the glass-ceramic, which led to an increase in the degree of polymerization of the matrix and a decrease in the activation energy of the crystallization, which promoted the crystallization process. Higher temperatures provided more energy for the crystal crystallization reaction and facilitated the process. The glass-ceramics showed good solidification of heavy metals and compliance with the requirements for various heavy metals in the toxicity leaching test. The glass-ceramic made from zinc leaching residue eliminated the risk of heavy metals contamination and was a green, harmless, high-performance material that can be used in a wide range of fields.

Electrical and ionic conductivity of Li2O-B2O3-Al2O3 glass electrolyte for solid-state batteries

Solid-state electrolyte is a key component for all-solid-state lithium-ion batteries. The Li2O-B2O3-Al2O3 has been prepared, which is co-sinterable with electrode due to its low sintering temperature (520 °C). The as-prepared Li2O-B2O3-Al2O3 reveals glass transition temperature of 420 °C and crystallization temperature of 462 °C. The Li2O-B2O3-Al2O3 possess the reasonable electrochemical performances such as lithium-ion conductivity of 3.075 × 10−5 S/cm, activation energy of 0.72 eV, electronic conductivity of 4.102 × 10−5 S/cm. It is attributed to the particle morphology, grain-to-grain bonding and non-bridging oxygen. Our finding demonstrates that Li2O-B2O3-Al2O3 is an effective breakthrough in solid electrolyte for good electrochemical performances as well as excellent interfacial contact through co-sintering.

Effects of oxygen loading on the red-luminescence of non-bridging oxygen hole centers in γ-irradiated silica glasses

Ultra-high purity Corning 7980 and Corning 7979 silica glasses, respectively with high and low contents of hydroxyl and hydrogen, were specifically selected to investigate the effects of O2 loading on the 1.9 eV red luminescence of the gamma-ray induced non-bridging oxygen hole center (NBOHC), whose luminescence intensity is beneficial not only to predict the laser damage of silica but also to the targeted improvements in the preparation-treatment processes of silica. The UV trasmittance spectra, the UV excitation spectra, the visible emission spectra and the red emission lifetime decay curves were determined for these two types of the gamma-ray irradiated silica glasses before and after O2 loading. The content ratios of Si dangling bond (Si-E′) to NBOHC in silica glasses before and after O2 loading are estimated. The formation precursors and other related defects for NBOHC, such as Si-E′, Si-O-Si bond, Si-O-H bond, peroxy radical and linkage, oxygen-deficient centers ODC(I) and ODC(II), etc, are discussed. The bandwidths of the excitation and emission spectra before and after O2 loading are compared at the lower energy side of the spectra. The average emission lifetimes and especially the decay curves of the red luminescence before and after O2 loading are analyzed. There appear two types of NBOHCs with and without neighbouring hydrogen interaction at room temperature, respectively corresponding to the shorter and longer lifetime components. After O2 loading, the shorter lifetime component disappears and becomes the longer one, indicating that the hydrogen-bonded NBOHC is altered into the non-bonded. It is suggested that the analysis of the shorter and longer lifetime components of the red luminescence can be utilized in the laser damage prediction as well as the preparation and treatment processes of silica.

A Dual Anion Chemistry-Based Superionic Glass Enabling Long-Cycling All-Solid-State Sodium-Ion Batteries.

Glassy Na-ion solid-state electrolytes (GNSSEs) are an important group of amorphous SSEs. However, the insufficient ionic conductivity of state-of-the-art GNSSEs at room temperature lessens their promise in the development of all-solid-state Na-ion batteries (ASSNIBs) with high energy density and improved safety. Here we report the discovery of a new sodium superionic glass, 0.5Na2 O2 -TaCl5 (NTOC), based on dual-anion sublattice of oxychlorides. The unique local structures with abundant bridging and non-bridging oxygen atoms contributes to a highly disordered Na-ion distribution as well as low Na+ migration barrier within NTOC, enabling an ultrahigh ionic conductivity of 4.62 mS cm-1 at 25 °C (more than 20 times higher than those of previously reported GNSSEs). Moreover, the excellent formability of glassy NTOC electrolyte and its high electrochemical oxidative stability ensure a favourable electrolyte-electrode interface, contributing to superior cycling stability of ASSNIBs for over 500 cycles at room temperature. The discovery of glassy NTOC electrolyte would reignite research enthusiasm in superionic glassy SSEs based on multi-anion chemistry.

Effect of La2O3–CeO2 codoping on the microstructure and mechanical properties of tailing glass–ceramics

The effect of the La2O3–CeO2 content on the microstructure and mechanical properties of CaO–MgO–Al2O3–SiO2 tailing glass–ceramics codoped with La2O3 and CeO2 was investigated to gain insight into the properties of glass–ceramics produced from solid wastes. The results showed that augite was the dominant crystalline phase in all of the samples. Augite formed a solid solution phase containing La and Ce as the La2O3–CeO2 content increased, and the shape of the augite phases changed from dendritic to island-shaped because La oxyapatite precipitated at the augite boundary. Among the glass–ceramics, the highest percentage of Si–O tetrahedrons with two nonbridging oxygen atoms (Q2) was observed for that containing 1 wt% La2O3–CeO2. In addition, this particular composition exhibited an optimal microstructure owing to its high crystallinity and interlocking dendrites. Consequently, this microstructure displayed superior mechanical properties, such as Vickers hardness, bending strength, and fracture toughness of 7.95 GPa, 250.13 MPa, and 1.97 MPa/m1/2, respectively.

Effect of BaF2 and Y2O3 on the Raman scattering characteristics of fluorotellurite glasses

In this letter, we investigated the Raman scattering characteristics of a series of aTeO2-(90-a)BaF2-10Y2O3 (a = 85, 80, 75, 70, 65, 60, 55 mol%), bTeO2-(95-b)BaF2-5Y2O3 (b = 90, 85, 80, 75, 70, 65, 60, 55, 50 mol%) and cTeO2-(100-c)BaF2 (c = 95, 90, 85, 80, 75, 70, 65, 60 mol%) fluorotellurite glasses. With increasing the concentration of BaF2, the peak Raman gain coefficient at 785 cm−1 increased while the Raman gain bandwidth (full spectral width at half maximum of the Raman peaks around 785 cm−1) decreased, which was attributed to the increasing proportion of non-bridge oxygen bonds in the fluorotellurite glass systems. The same results were also observed for the case of the increasing of the concentration of Y2O3. In these samples, the 50TeO2-40BaF2-10Y2O3 glass has the largest Raman gain coefficient of 29.9 × 10−13 m/W, and the 95TeO2-5BaF2 glass has the widest Raman gain bandwidth of 7.35 THz for the pumping laser at 633 nm. Furthermore, the first-order Raman Stokes light peaked at ∼2373 nm was obtained by using fluorotellurite fiber based on the above glasses as Raman gain medium and a 2000nm picoseconds laser as pump light. Our results provide guidance for further improving the performance of Raman fiber lasers or amplifiers based on fluorotellurite fibers.