Inorganic Glasses Research Articles

Understanding the Compositional Control on Electrical, Mechanical, Optical, and Physical Properties of Inorganic Glasses with Interpretable Machine Learning

Understanding the Compositional Control on Electrical, Mechanical, Optical, and Physical Properties of Inorganic Glasses with Interpretable Machine Learning

Mapping short-range order at the nanoscale in metal-organic framework and inorganic glass composites.

Characterization of nanoscale changes in the atomic structure of amorphous materials is a profound challenge. Established X-ray and neutron total scattering methods typically provide sufficient signal quality only over macroscopic volumes. Pair distribution function analysis using electron scattering (ePDF) in the scanning transmission electron microscope (STEM) has emerged as a method of probing nanovolumes of these materials, but inorganic glasses as well as metal-organic frameworks (MOFs) and many other materials containing organic components are characteristically prone to irreversible changes after limited electron beam exposures. This beam sensitivity requires 'low-dose' data acquisition to probe inorganic glasses, amorphous and glassy MOFs, and MOF composites. Here, we use STEM-ePDF applied at low electron fluences (10 e- Å-2) combined with unsupervised machine learning methods to map changes in the short-range order with ca. 5 nm spatial resolution in a composite material consisting of a zeolitic imidazolate framework glass agZIF-62 and a 0.67([Na2O]0.9[P2O5])-0.33([AlO3/2][AlF3]1.5) inorganic glass. STEM-ePDF enables separation of MOF and inorganic glass domains from atomic structure differences alone, showing abrupt changes in atomic structure at interfaces with interatomic correlation distances seen in X-ray PDF preserved at the nanoscale. These findings underline that the average bulk amorphous structure is retained at the nanoscale in the growing family of MOF glasses and composites, a previously untested assumption in PDF analyses crucial for future non-crystalline nanostructure engineering.

Heat resistance of solid inorganic glass cylinders

Heat resistance of solid inorganic glass cylinders

Estimation of the temperature band characterizing the liquid--glass transition interval for chalcogenide glasses

The temperature dependence of the viscosity of inorganic glasses in the glass transition region is successfully described by the Williams--Landel--Ferry (WLF) equation. For the studied glasses, the value of f_g=1/C1 weakly depends on the nature of the glasses. There is a linear correlation between delta delta Tg and Tg. From the data on the parameters of the WLF equation C1 and C2, we calculated delta delta Tg, as well as the relaxation time of the structure taug at the glass transition temperature of the glasses under study. Keywords: Viscosity in the glass transition region, Williams--Landel--Ferry equation, kinetic glass transition criterion, chalcogenide glasses, fluctuation volume fraction, liquid--glass transition.

The feasibility of jet fan-assisted ventilation for temperature control of heating belts on a downward-facing sphere in a scientific facility

To avoid the deformation of the large-scale scientific facility for neutrinos detection due to temperature changes, the heat generated during the top-down annealing of the inorganic glass panels needs to be released in time to maintain temperature control of 21±1°C in the built-up area. Due to the unique shape and the changing heating sources, a novel ventilation strategy that combines jet fans with general ventilation was proposed to satisfy the special environmental control requirement. A small-scale field experiment was conducted to obtain the CFD methods for simulation. Then, the feasibility of the jet fan-assisted ventilation system was discussed in terms of two thermal control zones based on the distance from the heat source. Besides, the effectiveness of the proposed ventilation design was compared with traditional general ventilation with air-conditioned air supplied from the hall ceiling and directly opposite the heating belt based on the temperature and velocity distribution. The results show that: the area outside the thermal control range under jet fan-induced ventilation was reduced by around 60%, and the maximum temperature fluctuated over time within 0.33°C. These results provide a preliminary insight into the use of jet fan-assisted ductless ventilation to achieve precision local temperature control in a large space.

Luminescence and structural evolution in ultra‐low melting quaternary tin fluorophosphate glasses (NaF‐SnF2‐SnO‐P2O5)

AbstractFor transparent low melting inorganic glass, which is relevant for sealing and additional applications, Pb‐containing glasses have reached the lowest melting point and best comprehensive performance. Considering potential toxicity and regulatory limitations, there is urgent need to develop Pb‐free ultra‐low melting point glass. Herein, we systemically investigated the structure and luminescence evolution of the Pb‐free ultra‐low melting quaternary tin fluorophosphate glasses (NaF‐SnF2‐SnO‐P2O5), in which varied NaF content was tuned to affect the properties of glass. With NaF content increases, the Sn‐O and P‐O bonds have been gradually transformed to Sn‐F and P‐F bonds, and the phosphrous tetrahedron PO4 has been converted to PO3F. The weaken bonding results in the decrease of the ultra‐low melting point to 329°C when NaF increased to 15 a.t.%, 29oC lower than the ternary glass. The blue shifts of both absorption and photoluminescence spectra were observed due to the higher ionic character of glass structure with NaF increases. As reported previously in the ternary tin fluorophosphate glass, the quaternary glass system also shows a phosphorescence behavior (∼1 s) due to the existence of oxygen vacancies. Additionally, the changes in oxygen vacancy defects correlate with the NaF content, thus affecting the decay time as well. The ultra‐low melting point luminescent quaternary tin fluorophosphate glasses (NaF‐SnF2‐SnO‐P2O5) may be relevant for opto‐electronic applications such as the packaging in displays or light‐emitting diodes.

Analysis of Fine Glass Waste Addition as a Filler Material for Sand Substitution on the Properties of Mortar Products

Inorganic glass waste can replace sand in mortar production due to its SiO 2 content being greater than 70%. This study aims to analyze the increase in mortal product agility due to the substitution of sand and reducing environmental pollution. The fine glass waste used is restrained on 80 and 120 mesh sieves. The fine glass waste substitution variations are 0, 10, 20, 30, 40, and 50% of the sand weight. The results show that fine glass waste could be used as a material for sand substitution because of the content of SiO2 of 73.8%. The results from XRD indicate that the phase of fine waste glass is amorphous. The mortar was printed with a 5x5x5 cm cube mold, and it was soaked for 7, 14, and 21 days. Based on the results, the compressive strength with a high value of 13.58 MPa at 20% fine glass waste substitution and 120 mesh. The density of 2.8±0.8 g/cm 3 , porosity 4.40±0.001%, and absorption 2.83±0,0009%. The compressive strengths, density, porosity, absorption, XRF and XRD characterization were evaluated. The results showed that the SiO 2 compound in waste glass with the right composition of 20% could significantly increase the compressive strength. Phase formation of Calcite (CaCO 3 ), Quartz (SiO 2 ), and Portlandite (Ca(OH) 2 ) was formed from the results of XRF characterization

Aggregation-induced emission fluorophore doped phosphate glass: Toward light-emitting electrochemical cells

Light-emitting electrochemical cells (LECs) are an easy-to-fabricate electroluminescent device, which in its simplest manifestation comprises an electroluminescence organic fluorophore and electrolytes as the active layer sandwiched between two electrodes. The LEC exhibits poor operational stability, and the poor thermal stability of the electrolyte is a major cause of the instability. Because most of the electrolytes utilized in LEC are organic electrolytes (polymer and ionic liquids), the thermal stability is difficult to improve on a large scale. Therefore, in this work, we are devoted to preliminarily exploring the possibility of using an inorganic glass electrolyte for LEC application. Following this objective, organic fluorophore (π-extended phosphole sulfide 1) doped inorganic phosphate amorphous matrix was successfully synthesized using spark plasma sintering technology. The optical properties, microstructure, and electrochemical properties of the hybrid glass were investigated, respectively. The ionic conductivity of the glass host can reach 10−7 S/cm at room temperature, and the glass matrix contain aggregates of 1 of around 100 nm. Strong photoluminescence at 600 nm, characteristic of the organic fluorophore, was observed in the hybrid glass. The cyclic voltammetry performed on the hybrid glass shows a redox couple contribution of the organic fluorophore. The result suggests 1 can complete the exchange of electric charges in the inorganic glass electrolyte, which is one of the fingerprints of the transient phenomena of a LEC.

Transition Metals (Cr3+) and Lanthanides (Eu3+) in Inorganic Glasses with Extremely Different Glass-Formers B2O3 and GeO2.

Glasses containing two different network-forming components and doped with optically active ions exhibit interesting properties. In this work, glass systems based on germanium dioxide and boron trioxide singly doped with lanthanides (Eu3+) and transition metals (Cr3+) ions are research subjects. Optical spectroscopy was the major research tool used to record excitation and emission spectra in a wide spectral range for studied systems. The emitted radiation of glasses doped with Cr3+ ions is dominated by broadband luminescence centered at 770 nm and 1050 nm (4T2 → 4A2). Interestingly, the increase of concentration of one of the oxides contributed to the detectable changes of the R-line (2E → 4A2) of Cr3+ ions. Moreover, EPR spectroscopy confirmed the paramagnetic properties of the obtained glasses. The influence of molar ratio GeO2:B2O3 on spectroscopic properties for Eu3+ ions is discussed. The intensity of luminescence bands due to transitions of trivalent europium ions as well as the ratio R/O decrease with the increase of B2O3. On the other hand, the increase in concentration B2O3 influences the increasing tendency of luminescence lifetimes for the 5D0 state of Eu3+ ions. The results will contribute to a better understanding of the role of the glass host and thus the prospects for new optical materials.

Structural Analysis of Molecular Materials Using the Pair Distribution Function.

This is a review of atomic pair distribution function (PDF) analysis as applied to the study of molecular materials. The PDF method is a powerful approach to study short- and intermediate-range order in materials on the nanoscale. It may be obtained from total scattering measurements using X-rays, neutrons, or electrons, and it provides structural details when defects, disorder, or structural ambiguities obscure their elucidation directly in reciprocal space. While its uses in the study of inorganic crystals, glasses, and nanomaterials have been recently highlighted, significant progress has also been made in its application to molecular materials such as carbons, pharmaceuticals, polymers, liquids, coordination compounds, composites, and more. Here, an overview of applications toward a wide variety of molecular compounds (organic and inorganic) and systems with molecular components is presented. We then present pedagogical descriptions and tips for further implementation. Successful utilization of the method requires an interdisciplinary consolidation of material preparation, high quality scattering experimentation, data processing, model formulation, and attentive scrutiny of the results. It is hoped that this article will provide a useful reference to practitioners for PDF applications in a wide realm of molecular sciences, and help new practitioners to get started with this technique.

Multiphoton upconversion and non-resonant optical nonlinearity in perovskite quantum dot doped glasses.

By incorporating the CsPbBr3 quantum dots (QDs) into a glass host, we report for the first time, to our knowledge, the measurement of non-resonant optical nonlinearity and multiphoton upconversion (UC) processes for this QD-in-glass composite. We observe up to four-photon stable UC photoluminescence under excitation by infrared femtosecond pulses, low optical limiting thresholds, and high nonlinear optical absorption coefficients close to those of colloid processed metal halide perovskite (MHP) QDs. Combined with high robustness against air and moisture, the monolithic inorganic glass with incorporated MHP QDs could be a better platform for exploiting strong light-matter interaction for MHPs.

Strategies for the surface biofunctionalization of sulfur-based chalcogenide infrared optical glasses

Effective surface functionalization plays a critical role in the selectivity and sensitivity of sensing devices. While chalcogenide glasses (ChG) have received a lot of attention as promising optical materials for mid-IR biosensors, there have been just a few reported instances of their successful (bio)functionalization. In the present work, we explore three different approaches for the grafting of heterobifunctional derivatives on Ge25Sb10S65 substrates. One of these approaches consisted in the use of traditional silane chemistry to functionalize hydroxyl moieties on the ChG, while the other two are novel strategies based on the potential reactivity of maleimide and cyclooctyne derivatives for sulfhydryl moieties at the surface of the inorganic glass matrix. Using these approaches, biotinylated surfaces were prepared and the selective grafting of a fluorescent-labeled protein was then validated via IR spectroscopy, AFM and fluorescence. Our results showed that successful biofunctionalization of Ge-Sb-S ChG was achieved by all three methods. Moreover, the functionalization process can be easily adapted for substrates with any type of geometry and for the grafting of different molecules at the surface, paving the way for the future development of infrared optical sensing systems exhibiting surface bio selectivity.

An improved material model for loading-path and strain-rate dependent strength of impacted soda-lime glass plate

The main purpose of this work is to develop a macro material constitutive model for inorganic glass response description under impact conditions. Firstly, the quasi-static and dynamic strength of soda-lime glass was obtained through uniaxial compression and combined compression-shear loading tests. The strain-rate and loading-path dependence of glass strength was observed from these experimental results. An improved model of impacted soda-lime glass plate was proposed based on the JH-2 model including the loading-path influence through an additional factor as a function of the Lode parameter. In commercial code Abaqus, the improved model is implemented through a user-defined material subroutine. Additionally, simulation of the static test, SHPB test, and impact test on glass specimens respectively is conducted to validate the model with updated material constants. The comparisons illustrate that the improved model of soda-lime glass provides better accuracy and efficiency predictions of glass responses at various loading conditions.

Narrow-gap, semiconducting, superhard amorphous carbon with high toughness, derived from C60 fullerene

New carbon forms exhibiting extraordinary physico-chemical properties can be generated from nanostructured precursors under extreme pressure. Nevertheless, synthesis of such fascinating materials is often not well understood that results, as is the case of C60 precursor, in irreproducibility of the results and impeding further progress in the materials design. Here the semiconducting amorphous carbon having bandgaps of 0.1-0.3 eV and the advantages of isotropic superhardness and superior toughness over single-crystal diamond and inorganic glasses are produced from transformation of fullerene at high pressure and moderate temperatures. A systematic investigation of the structure and bonding evolution was carried out by using rich arsenal of complimentary characterization methods, which helps to build a model of the transformation that can be used in further high p,T synthesis of novel nanocarbon systems for advanced applications. The produced amorphous carbon materials have the potential of demanding optoelectronic applications that diamond and graphene cannot achieve

Infrared Luminescent Hybrid Materials Based on Inorganic Glass Matrices

Infrared Luminescent Hybrid Materials Based on Inorganic Glass Matrices

Nanoscale Engineering of Inorganic Composite Scintillation Materials

This review article considers the latest developments in the field of inorganic scintillation materials. Modern trends in the improvement of inorganic scintillation materials are based on engineering their features at the nanoscale level. The essential challenges to the fundamental steps of the technology of inorganic glass, glass ceramics, and ceramic scintillation materials are discussed. The advantage of co-precipitation over the solid-state synthesis of the raw material compositions, particularly those which include high vapor components is described. Methods to improve the scintillation parameters of the glass to the level of single crystals are considered. The move to crystalline systems with the compositional disorder to improve their scintillation properties is justified both theoretically and practically. A benefit of the implementation of the discussed matters into the technology of well-known glass and crystalline scintillation materials is demonstrated.

Extracting processing and testing parameters from materials science literature for improved property prediction of glasses

Recent literature has seen a surge in artificial intelligence (AI) and machine learning (ML) for computational design and discovery of novel materials. Most of these studies focus on inverse design or property prediction through composition–structure–property relationships. However, a crucial aspect that has received less attention is the materials' processing route and testing conditions. Here, we present a framework combining text-mining with ML, enabling extraction of processing and testing conditions in addition to the material composition for improved property prediction. We demonstrate this framework by predicting the hardness of inorganic glasses with composition, annealing temperature, and loading conditions as input. Specifically, we analyze the text associated with research articles to obtain the process parameters of oxide glasses with various input components. We show that process parameters and composition together as input yield superior predictions of hardness. Interpreting the predictions using a game-theoretic approach, namely SHAP, we show that the processing and testing parameters indeed play a significant role in controlling the hardness of glasses. Finally, we show that the proposed approach can outperform heuristic approaches for glass synthesis, allowing scientists to choose the most appropriate synthesis route for developing glasses with targeted properties.

Evaluation of the Atom Delocalization Energy in Inorganic Glasses

Evaluation of the Atom Delocalization Energy in Inorganic Glasses

Vitrification of octonary perylene mixtures with ultralow fragility.

Strong glass formers with a low fragility are highly sought-after because of the technological importance of vitrification. In the case of organic molecules and polymers, the lowest fragility values have been reported for single-component materials. Here, we establish that mixing of organic molecules can result in a marked reduction in fragility. Individual bay-substituted perylene derivatives display a high fragility of more than 70. Instead, slowly cooled perylene mixtures with more than three components undergo a liquid-liquid transition and turn into a strong glass former. Octonary perylene mixtures display a fragility of 13 ± 2, which not only is a record low value for organic molecules but also lies below values reported for the strongest known inorganic glass formers. Our work opens an avenue for the design of ultrastrong organic glass formers, which can be anticipated to find use in pharmaceutical science and organic electronics.

Gadolinium contained scintillation glass for neutron detection in a wide energy range.

Inorganic scintillation glasses form a domain of rapidly evolving detector materials used to measure various types of ionizing radiation. The most widespread are lithium-silicate glasses enriched with the 6Li isotope, which are used to register thermal neutrons. At the same time, due to the specificity of the energy dependence of the neutron cross-section of light nuclei, such materials are of little use for the evaluation of epithermal and more highly energetic neutrons. The use of rare earth elements in the composition of glasses makes it possible to increase the sensitivity to neutrons. In the BaO–Gd2O3–SiO2 system, doped with Ce ions, a scintillation glass with a yield of at least 2500 photons / MeV was created for the first time, which permits to create inexpensive detector elements of a significant volume for registering neutrons. It has been shown that a detector based on BaO–Gd2O3–SiO2 glass has satisfactory properties when detecting neutrons in a wide spectrum of their energies.