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Chiral organic glasses combine unique optical properties with the processing advantages of amorphous solids. Here, melt‐quenching as a strategy for preparing optically active glasses from enantiopure BINAP (2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl), a pivotal ligand in asymmetric catalysis and for luminescent metal complexes is demonstrated. Thermal characterization reveals that only R‐BINAP and S‐BINAP, not rac‐BINAP, form molecular glasses with glass transition temperatures near 100 °C. Pair distribution function analysis and circular dichroism confirm the retention of local structure and homochirality despite the loss of long‐range order. Remarkably, the glassy state has a beneficial influence on the molecular optoelectronic properties relative to the crystalline state, resulting in an increase of the radiative rate constant by ≈30%, attributed to more favourable Franck‐Condon factors. In addition, a highly unusual simultaneous enhancement of circularly polarized luminescence (CPL) by nearly an order of magnitude is observed, achieving dissymmetry factors |glum| approaching 10−2 that are competitive with the top‐performing purely organic molecular chiral emitters reported to date. These findings establish melt‐quenched chiral molecular glasses as promising platforms for advanced optoelectronic and photonic materials, combining exceptional chiroptical properties, strong luminescence, and processability without the constraints of crystallinity. Melt‐quenching of enantiopure BINAP yields transparent chiral molecular glasses that retain axial chirality and display blue‐shifted luminescence together with strongly enhanced circularly polarized emission with dissymmetry factors |glum| of ≈10−2. These materials unite optical clarity, strong emission, and high chiroptical activity, highlighting vitrification as a powerful strategy for creating solid‐state chiral photonic materials.

The effect of CuO on the structural, optical, dielectric, and radiation shielding properties of copper fluorobarioborate (CFBB) glasses synthesized by the melt-quench technique with a general composition xCuO–(50 − x)B 2 O₃–35BaO–15MgF₂ (0–0.5 mol%) was investigated. XRD measurements indicated that all the samples, except those with higher values of CuO, were amorphous in nature. FTIR studies exhibited stable BO₃, BO₄, and B–O–B units, indicating an insignificantly modified borate network. The UV–Vis spectral studies showed enhanced UV absorption with the increase in the concentration of CuO. The value of both the direct and indirect optical band gaps is found to be almost the same (3.48–3.60 eV). Dynamic measurements of dielectric properties showed strong frequency dispersion, characterized by decreased ε′ and ε′′ and conductivity behavior based on hopping mechanisms. The radiation shielding parameters show high attenuation at low photon energies and improved shielding for CFBB glasses with increased CuO content. Hence, CFBB glasses have sufficient promise for optical transparency coupled with stable dielectric behavior and effective γ-ray attenuation. The novelty of this study is in simultaneous investigations concerning optical clarity, dielectric stability, and shielding efficacy in low CuO-doped fluorobarioborates, emphasizing their potential usage in multiple ways due to their multifunctionality.

A novel series of Fe 3+ doped mixed alkali zirconia-borate glasses with the composition 60B 2 O 3 –25Na 2 O–10Li 2 O–(5 − x)ZrO 2 –xFe 2 O 3 (x = 0–1 mol%) were synthesized using the melt-quenching technique. The novelty of this work lies in combining the structural modifications with enhanced optical properties and orange-red luminescence in Fe 3+ doped mixed alkali zirconia-borate glasses for warm photonic applications. X-ray diffraction confirmed the non-crystalline nature of glass, while SEM images and EDS spectra were utilised for morphological and elemental analysis. The density of the glasses decreased from 2.4197 to 2.4168 g cm −3 before gradually increasing to 2.4324 g cm −3 . FTIR and Raman spectral studies showed the formation of non-bridging orthoborate units from pentaborate and di-pentaborate units. The optical absorption band at 450 nm is associated with the Fe 3+ transition 6 A 1g ( 6 S) →  4 A 1g ( 4 G); 4 E g ( 4 G). The decrease in direct bandgap from 3.90 to 3.10 eV and indirect bandgap from 3.44 to 2.77 eV, along with an increase in Urbach energy from 0.245 to 0.273 eV, indicates the disorder in structure. An increase in refractive index leads to an increase in third-order susceptibility and nonlinear refractive index. The photoluminescence spectra exhibited orange-red emission at ( 4 T 2g ( 4 G) →  6 A 1g ( 6 S)) with 550 nm, 560 nm and 570 nm excitation wavelengths. The CIE chromaticity and CCT values show that Fe 3+ doped glasses are suitable for warm-emitting orange-red photonic applications.

Composition glass with x Quartz Sands+(60– x )P 2 O 5 +10BaO+30Na 2 O (%mol) with ( x = 0; 2,5; 10; 5; 10; 15; 20) and 15mol% was tested using melt-quenching technique and ball mill technique to refine quartz sand. A few of the characterization carried out distinguish physical properties and basic properties. Characterization using XRD to shows the purity of the high silicate content in quartz sand and shows that QSand-Phosphate glass has an amorphous structure after all samples are mixed. FTIR to show that QSand-Phosphate glass from Hutaginjang has a maximum transmittance absorption band but with different strain widths and heights in vibration absorption as the quartz sand increases. Based on the results of their radiation properties, the glasses in this study has the potential as optical amplifier.

The synergistic effect between strontium (Sr) and melt quenching on the solidified microstructure of hypereutectic Al-Si alloys was investigated by optical and scanning electron microscopy. The results indicate that melt quenching can suppress the growth of primary Si particles in the solidified structure of the hypereutectic Al-Si alloy, resulting in a significant decrease of in the average size of primary Si particles in Al-(18~22)Si alloys from 30.35~66.31 μm to 15.13~34.63 μm. The synergistic effect between Sr and melt quenching can further inhibit the precipitation of primary Si particles in the Al-18Si alloy. After the addition of Sr to Al-18Si alloy and undergoing melt quenching, the area fraction of primary Si clearly decreases. When the added amount of Sr increases from 0.1 wt.% to 0.5 wt.%, the area fraction of primary Si decreases from 1.13% to 0.16%. With 0.5 wt.% Sr in the tested alloy, the inhibiting effect on primary Si precipitation was significantly improved. Research has shown that the cooling rate has a significant impact on the solidified structure of the melt-quenched Al-18Si-0.5Sr alloy. There exists no primary Si in solidified structures on the area of 1/8R and 1/4R from the surface of the round bar sample, but the area fraction of primary Si increases, respectively, to 1.97% and 12.48% on the area of 1/2R and R from the surface. The higher the cooling rate, the higher the inhibitory effect on the primary Si precipitation in the Al-18Si-0.5Sr alloy.

The aim of this study was to investigate the structural and optical properties of mixed alkaline earth fluoroborate glasses with compositions of x BaF 2 –(50– x) CaF 2 –50B 2 O 3 ( x  = 5–30 mol%) synthesized using the melt-quenching technique. The glass characterization included X-ray diffraction (XRD), Fourier transform infra-red (FTIR), and optical absorption spectra analysis. Based on the XRD results, the absence of a sharp peak at x  = 5–30 mol% indicated the absence of long-range order and confirmed the glass matrix's amorphous nature. Furthermore, the FTIR spectroscopy revealed that the replacement of calcium fluoride (CaF 2 ) with barium fluoride (BaF 2 ) in the network resulted in the alteration of trigonal boron (BO 3 ) units into tetrahedral B 4 units, which contained tetrahedral boron (BO 4 ) and oxyfluoroborate tetrahedral (BO 3 F) units. Moreover, the energy bandgap ( E opt ) varied from 3.18 to 3.58 eV for direct transition and from 2.74 to 3.12 eV for indirect allowed transition. Both E opt increased from x  = 5–30 mol% with a sharp increase from x  = 15–20 mol%. The increase of both E opt was due to the increase in bridging oxygen formation, while the sharp increase at 15 ≤  x  ≤ 20 mol% was associated with the abrupt decrease in nonbridging oxygen (NBO) due to the mixed alkaline earth effect (MAEE) in the region. Meanwhile, the decrease in refractive index from 2.35 to 2.26 with a sharp drop between 15 and 20 mol% was associated with the decrease in electron packing density and the lower polarizing power of BaF 2 compared to CaF 2 . The electronic polarizability of oxide/fluoride ions and optical basicity showed an anomalous minimum at 25 mol%, suggesting the influence of MAEE on both properties in the region. This study concluded that the mixed alkaline earth fluoroborate glass synthesized using the melt-quenching technique demonstrated the presence of MAEE through the anomalies in the structural and optical parameters of the presently studied glasses.

This research addresses the significant challenges of waste disposal and the need for sustainable production in the ceramics industry by introducing an approach to fabricating calcium-alumino-silicate-fluoride (CASF) based glass ceramics. Using recyclable materials such as waste soda-lime-silicate (SLS) glass and clam shells (CS) as primary precursors, a controlled melt-quenching process was employed to investigate how varying the CaO/CaF 2 ratios influences the physical and structural properties of CASF glass ceramics. The waste materials and CASF glass ceramics were analyzed using X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transforms infrared (FTIR), Scanning electron microscopy (SEM), and Energy dispersive X-ray (EDX) spectroscopy. XRD indicated the crystalline structure in all CASF glass ceramics samples while FTIR spectroscopy detected several linkages, including PO 4 3− , Si-OH, Si-O-Si, CO 2 , and O-H indicating the development of CASF glass ceramics. SEM analysis showed a non-uniform distribution of particles and EDX analysis, shows the calcium-to-phosphate molar ratio (Ca/P) of CASF glass ceramics. The glass ceramics labeled as G6 possessed better properties, with a minor crystalline phase identified as fluorapatite (Ca 5 (PO 4 ) 3 F), which is compatible with the commercial bioglass. These results demonstrate a cost-effective waste-derived bioglass system used in biomedical fields.

Calcium oxide from discarded eggshells and waste soda-lime-silica were utilized in this study to make wollastonite (CaSiO3) based glass-ceramics. The calcium oxide and silica were made using the melt-quenching process and sintered for 2 hours at 700 to 1000 ?C. The XRD data verified that the wollastonite crystalline peak appeared at high sintering temperatures, with crystalline phase values of 39.74%, 47.37%, and 48.91% as the sintering temperature increased at 800-1000?C, respectively. Additionally, crystalline size and phase have no obvious change at 800-1000?C, where the intensity has increased by the sintering temperature. The FTIR spectra revealed the wollastonite phase vibration at the wavelength of 501, 650, 715, 808, 931, and 2129 cm-1. Additionally, the FTIR spectral confirm the Si-O-Ca vibration band at the wavelength of 650 cm-1. For the optical sample, the value of indirect allowed transition with n=2 is the ideal value of the optical band gap based on a band gap rise from 3.89 to 4.23 eV with increasing sintering temperature. The value n=2 which is the indirect allowed transition is the optimal value of the optical band gap based on the value increase from 3.89-4.23 eV as the temperature increase. The synthesis approach introduced the low-cost method, recycle approach, simple and yet uses cheap starting materials for fabrication of wollastonite glass-ceramics product.

Zirconium doped calcium phosphate-based bioglasses are the most prominent bioactive materials for bone and dental repair and regeneration implants. In the present study, a 8ZnO–22Na2O–(24 − x)CaO–46P2O5–xZrO2 (0.1 ≤ x ≤ 0.7, all are in mol%) bioglass system was synthesized by the conventional melt-quenching process at 1100 °C. The glass-forming ability and thermal stability of the glasses were determined by measuring the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm), using differential thermal analysis (DTA). The biological activity of the prepared samples was identified by analyzing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-energy dispersive spectra (SEM-EDS), before and after immersion in simulated body fluid (SBF) for various intervals of 0, 1 and 5 days, along with the magnitude of pH and the degradation of glasses also evaluated. The obtained results revealed that the glass-forming ability and thermal stability of glasses increased with the increase in zirconia mol%. The XRD, FTIR, and SEM-EDS data confirmed a thin hydroxyapatite (HAp) layer over the sample surface after incubation in SBF for 1 and 5 days. Furthermore, the development of layer found to be increased with the increase of incubation time. The degradation of the glasses in SBF increased with incubation time and decreased gradually with the increase content of ZrO2 mol% in the host glass matrix. A sudden rise in initial pH values of residual SBF for 1 day owing to ion leaching and increase of Ca2+ and PO43− ions and then decreased. These findings confirmed the suitability of choosing material for bone-related applications.

The phenomenon of melting in metal–organic frameworks (MOFs) has recently garnered attention. Crystalline MOF materials can be transformed into an amorphous glassy state through melt-quenching treatment. The resulting MOF glass structure eliminates grain boundaries and retains short-range order while exhibiting long-range disorder. Based on these properties, it emerges as a promising candidate for high-performance separation membranes. MOF glass membranes exhibit permanent and accessible porosity, allowing for selective adsorption of different gas species. This review summarizes the melting mechanism of MOFs and explores the impact of ligands and metal ions on glassy MOFs. Additionally, it presents an analysis of the diverse classes of MOF glass composites, outlining their structures and properties, which are conducive to gas adsorption and separation. The absence of inter-crystalline defects in the structures, coupled with their distinctive mechanical properties, renders them highly promising for industrial gas separation applications. Furthermore, this review provides a summary of recent research on MOF glass composite membranes for gas adsorption and separation. It also addresses the challenges associated with membrane production and suggests future research directions.