Impact of bismuth oxide on the structure,optical features and ligand field parameters of borosilicate glasses doped with nickel oxide

Understanding the impact of bismuth cations on the optical properties of borosilicate glass is significant for manipulating borate glass applications. In this paper, the influence of bismuth cations on both structural and optical properties of borosilicate glass doped with NiO was investigated. Different glass samples, containing different amounts of Bi₂O₃ and a constant amount of NiO, were prepared and studied. Infrared (IR) analysis was carried out to study the internal structure within the investigated glass samples. Optical absorption studies were performed to investigate the impact of Bi₂O₃ content on optical properties of the BiBaNiB-glasses. Astonishingly, with Bi₂O₃ addition, an absorption band at 380 nm has appeared. Moreover, this band is overlapped with the Urbach edge; which regularly produced an artificial edge-like feature at ~450 nm. A detailed deconvolution protocol has been implemented for an appropriate understanding of these spectra and unraveling the hidden Urbach edge. Optical band gap energy, linear and nonlinear refractive index for each BiBaNiB sample were calculated. Furthermore, the metallization criterion was calculated to examine the metallic or insulating nature of the BiBaNiB-glasses. The values of the nonlinear third-order susceptibility and nonlinear refractive index were increased with Bi₂O₃ doping. The BiBaNiB-glasses exhibited outstanding stability and optical band gap than the pristine glass sample, which makes it possible for practical applications.     

Effect of ZnO on the crystallization and photoluminescence of CsPbI3 perovskite quantum dots in borosilicate glasses

CsPbI₃ perovskite quantum dots (QDs) doped borosilicate glass was prepared by the process of melt-quenching and subsequent annealing. With the introduction of ZnO to the parent glass as the glass network intermediate, the optical properties of the resultant samples are dramatically enhanced. Both the photoluminescence (PL) intensity and photoluminescence quantum yield (PLQY) shows a strong dependence on ZnO concentration as ZnO is found to facilitate the precipitated of the QDs by reducing the connectivity of three-dimensional glass network built from SiO₄ tetrahedrons. The tunable visible-band PL emission of the CsPbI₃ QD-doped glass could find potential applications in white LEDs and lasers.     

Composition-structure-properties relationship of lithium-calcium borosilicate glasses studied by molecular dynamics simulation

The composition-structure-properties relationship of the lithium-calcium borosilicate (LCBS) glasses, which have a composition of 0.4[(1-x)Li₂O-xCaO]-0.6[(1-y)B₂O₃-ySiO₂] with x in the range of 0–1 and y in the range of 0.33–0.83, is investigated by the molecular dynamics (MD) simulation with the Buckingham potential. The structure of the silicon-oxygen tetrahedron is relatively independent of the glass compositions; however, the structure of the boron-oxygen polyhedron and the local environment around the modifier cations change significantly with increasing [SiO₂]/[B₂O₃] ratio (K) and CaO content. The relationships between glass composition and simulated linear thermal expansion coefficient (α_L), glass transition temperature (T_g), self-diffusivity (D), activation energy of electrical conductivity (Ea^σ) and fragility (m) are strongly affected by the change of glass network structure, and consistent with those of experimental results.     

Influence of molybdenum oxide on structural,optical and physical properties of oxychloride glasses for nonlinear optical devices

The unconventional Heavy Metal Oxide Glasses (HMOG) are characterized by a low phonon energy, large infrared range transmission, high refractive index and nonlinear optical properties. Ternary glasses have been synthesized and studied in the Sb₂O₃– MoO₃-ZnCl₂ system. Further, the glass formation compositional limits are reported and some glass samples with the formula: (90-x)Sb₂O₃ -xMoO₃–10 ZnCl₂ (10 ≤ x ≤ 50, mole%) were elaborated. Thermal properties have been measured and indicating that the glass transition temperature decreases with increasing proportions of molybdenum oxide. The evolution of density, microhardness and elastic modulus has been studied as functions of parameter x and Raman spectra measurements have been shown the partial conversion of MoO₆ octahedral units into MoO₄ tetrahedral.     

Preparation and photoluminescence properties of perovskite Cs4PbBr6/CsPbBr3 quantum dots integrated into lithium-borosilicate glass

Quantum dots (QDs), like all inorganic perovskite cesium lead bromide Cs₄PbBr₆ and CsPbBr_3, have shown potential as multifunctional optoelectronic materials. However, their lack of stability precludes any further practical uses from being developed. Glass as a carrier can effectively resolve these problems while retaining excellent luminescent properties. Herein, a novel perovskite Cs₄PbBr₆/CsPbBr₃ QDs embedded in lithium borosilicate glass was prepared. The phase transition mechanism of Cs₄PbBr₆/CsPbBr₃-based QDs in lithium-borosilicate glass with varying concentrations of Li₂O was investigated. Increases in the size and quantity of QDs with increasing contents of Li₂O were analyzed using transmission electron microscopy (TEM). A narrow photoluminescence (PL) emission band was observed, with a substantial emission intensity shift and a red-shifted luminescence peak. After 30 days of immersion in water, the QDs maintained approximately 84% of their luminescence intensity. According to the results, the perovskite Cs₄PbBr₆/CsPbBr₃ QDs embedded into lithium borosilicate glass have promising future applications in display technology.     

Environmental influence of high Na2O additions on microstructure and ligand field parameters of Cr3+ inside borosilicate glass

A glass system based on the Na₂O/B₂O₃-doped CrO₃ borosilicate has been prepared by the melt quenching technique. The structure, color, optical absorbance and ligand field parameters were investigated for a wide range of Na₂O additives (20–60 mol%). All X-ray photoelectron spectroscopy (XPS) profiles were used to study the chemical shift states of the glass-constituting elements. Fourier transform infrared (FTIR) analyses explored the internal structure and subnetwork units. Furthermore, from the FTIR results, we concluded the transformation of trigonal borate units (BO₃) to tetrahedral borate units (BO₄) and the possibility of transformation from B₃-O-Si linkages to B₄-O-Si linkages. Despite the fixed CrO₃ content, the doped glasses showed a color transition from green to yellow with additional Na₂O content. The increased intensity of the band at 451–427 nm and the decreased intensity of the band at 619–627 nm are the main reasons for this color transformation. The optical absorption spectra confirmed the existence of Cr³⁺ and Cr⁶⁺ states. A decreasing behavior for the crystal field splitting (10Dq) and an increasing behavior for Racah parameter (B) were obtained with further Na₂O additives. The decreasing behavior of 10Dq was attributed to reduced oxygen concentrations with more Na₂O/B₂O₃ substitutions. The increasing behavior of B reflects the tendency of the bond between the Cr cations and their oxygen ligands towards an ionic nature. Moreover, the Dq/B values indicated that Cr³⁺ cations are in high-field positions for the glass sample containing 20 mol% Na₂O, and Cr³⁺ cations are in intermediate field positions for the glass sample containing 30 mol% Na₂O. However, for the glass samples doped with 40, 50 and 60 mol% Na₂O glass samples, Cr³⁺-cations are in weak field positions. These results of (Dq/B) recommend the glass sample doped with 20 mol% Na₂O for tunable laser applications.     

Silver nanoparticles enhanced luminescence and stability of CsPbBr3 perovskite quantum dots in borosilicate glass

Series of silver nanoparticles (NPs) embedded CsPbBr₃ quantum dots (QDs) glass was synthesized via the melt-quench method. Ag NPs and CsPbBr₃ QDs coexist in the TEM image of the Ag-doped glass sample. Photoluminescence (PL) spectra show that the 0.1 molar ratio Ag₂O-doped sample had a PL intensity 2.37 times than the undoped sample. This increase is generated by localized surface plasmon resonance coupling between the Ag NPs and CsPbBr₃ QDs. Excessive Ag doping weakens the PL intensity due to spectral self-absorption of the Ag NP surface plasmon resonance (SPR). Self-adsorption of SPR is detrimental to luminescence properties because it increases the amount of photogenerated charge carriers, which proceed through nonradiative relaxation pathways. In addition, stability results of Ag NP-doped-CsPbBr₃ QD glass show that they have excellent stability. This study on Ag NP-doped-CsPbBr₃ QD glass provides a new idea for the future development of perovskite QD optoelectronic devices.     

Effects of optical dopants and laser wavelength on atom probe tomography analyses of borosilicate glasses

Atom probe tomography (APT) is a novel analytical microscopy method that provides three dimensional elemental mapping with sub‐nanometer spatial resolution and has only recently been applied to insulating glass and ceramic samples. In this paper, we have studied the influence of the optical absorption in glass samples on APT characterization by introducing different transition metal optical dopants to a model borosilicate nuclear waste glass. A systematic comparison is presented of the glass optical properties and the resulting APT data quality in terms of compositional accuracy and the mass spectra quality for two APT systems: one with a green laser (532 nm, LEAP 3000X HR) and one with a UV laser (355 nm, LEAP 4000X HR). These data were also compared to the study of a more complex borosilicate glass (SON68). The results show that the analysis data quality, particularly the compositional accuracy and sample yield, was clearly linked to optical absorption when using a green laser, while for the UV laser optical doping aided in improving data yield but did not have a significant effect on compositional accuracy. Comparisons of data between the LEAP systems suggest that the smaller laser spot size of the LEAP 4000X HR played a more critical role for optimum performance than the optical dopants themselves. The smaller spot size resulted in more accurate composition measurements due to a reduced background level independent of the material's optical properties.     

A promising optical limiting material: Tunable third-order nonlinear optical properties of robust CsPbX3 (X=Cl/Br,Br) nanocrystals glasses

As laser technology advances, the importance of laser protection puts an urgent demand for robust and high-efficient optical limiting materials. In this work, CsPbX₃ (X = Cl/Br, Br) NCs were synthesized by precisely controlling the ratio of Cl⁻ to Br⁻ and the heat treatment temperature, and the third-order nonlinear (TONL) optical properties of them were investigated systematically and deeply based on a nonlinear optical imaging technique with the phase-object (NIT-PO) at 532 nm for the first time. All of them demonstrate strong reverse saturation absorption (∼10^-12–10^-11 m/W), and the sign of TONL refraction index (γ) relates to the component (CsPb(Cl/Br)₃ NCs glasses: ∼10^-20 m²/W, CsPbBr₃ NCs glasses: ∼−10^-20 to 10^-19 m²/W). In addition, they have excellent characteristics of thermal stability and water stability, as well as photostability under 455 nm laser irradiation, indicating that it is a promising optical limiting material.     

Effect of Zr ions on the structure and optical properties of lithium borosilicate molybdate glass system

The glass system with the composition [(20-x) MoO₃– x ZrO₂–15 SiO₂– 65 Li₂B₄O₇, x = 0, 1, 2, 3, 4, and 5 mol %] was successfully synthesized using the melt quenching method. The XRD results of this glassy system confirmed the glassy nature of the prepared glasses. The density of this glassy system presented higher values while the molar volume provided lower values with increasing ZrO₂ content. The FTIR result showed that the spectrum of each sample consisted of broad bands that de-convoluted into several peaks. These peaks were characterized and the structure of each sample was recognized. Additionally, the optical measurements showed that sample x = 0 mol% provided a sharp ultra-violet cut-off at 380 nm, while the other samples showed a transition peak in the (210–230) nm range. The energy of optical band gaps of these glass samples decreased and the Urbach energy increased by increasing ZrO₂ content. Moreover, the different optical parameters of these glass samples were calculated and showed that the studied glasses could be considered promising materials to be used in different optical applications such as nonlinearity and optoelectronics.     

Effect of Y2O3 on the structural,optical and radiation shielding properties of transparent Na-rich borate glass with diluted and fixed Fe2O3

We study the impact of yttrium oxide (Y₂O₃) on the optical properties of iron-doped borate glasses. A series of borate glasses, with a diluted and constant amount of Fe₂O₃, doped with various amounts of Y₂O₃ (labeled as BNaFeY-glasses) was prepared and studied. The impact of Y₂O₃ doping on the optical transitions of BNaFeY-glasses was studied by analyzing the optical absorption spectra. The presence of Fe cations, with their Fe³⁺ state, leads to the appearance of absorption in the ultraviolet region. Furthermore, the optical transmittance spectra proved the transparency of all BNaFeY-glasses. Moreover, the transmittance of the sample with the highest Y₂O₃ content is about 93 % within the visible range. Because of the diluted Fe content within BNaFeY-glasses, the five absorption bands of Fe are not observed. So, these bands are detected by magnifying the spectra within the visible region. These bands are labeled ?₁, ?₂, ?₃, ?₄ and ?₅ at wavelengths 454.5, 518.4, 652.5, 707 and 808 nm respectively. These bands were used to calculate the crystal field splitting (10Dq) for all BNaFeY-glasses. The outstanding 10Dq increment with further Y₂O₃ doping was explained in terms of more interactions between Fe cations and their surroundings. On the other side, the shielding parameters were considered to examine the competence of these transparent glasses against nuclear radiation. We found that the sample doped with the highest amount of Y₂O₃ has the highest linear attenuation coefficient and the lowest half-value layer (HVL). From the HVL results, we need a thickness of 3.646 cm from the sample with 5 mol% of Y₂O₃ to get protection from 50% of the photons with energy of 0.662 MeV, and this thickness is increased to 5.137 cm when the energy is 1.333 MeV.     

Lead oxide enables lead volatilization pollution inhibition and phase purity modulation in perovskite quantum dots embedded borosilicate glass

Embedding all-inorganic cesium lead halide CsPbX₃ (X=Cl, Br, I) perovskite quantum dots (PQDs) PQDs into glass is one of the most effective strategies to improve their optical, thermal and chemical stabilities. Herein, by using PbO instead of PbBr₂ as the lead source, it is effective to lower the melting temperature and reduce the volatilization pollution from lead halide raw materials. Thus, a high-purity CsPbBr₃ PQDs embedded glass with 71.5 % PLQY was successfully prepared. The thermal stability, and photo-aging properties were also improved. By simply changing the halogen element, the red and blue CsPbX₃ PQDs embedded glasses were successfully prepared. The white LED fabricated by coating obtained green/red CsPbX₃ PQDs embedded glass on a blue chip displays high color gamut of 121.9 % NTSC standard and >91.1 % Rec. 2020 standard, which embodies the great potential of PQDs embedded glass in lighting and display fields.     

Thermal study of melting,transition and crystallization of rubidium and cesium borosilicate glasses

Thermal properties of the synthesized rubidium and cesium borosilicate glasses have been studied by differential scanning calorimetry. The values of glass transition temperature (T_g) and crystallization temperature (T_c) have been determined, the characteristic features of crystallization process have been established at various heat treatment conditions. Glass crystallization products have been characterized by powder X-ray diffraction. Information on the properties of the glasses makes it possible to correct the heat treatment parameters for glass-containing nuclear waste matrix materials.     

Effect of topological structure on photoluminescence of PbSe quantum dot‐doped borosilicate glasses

Borosilicate glasses doped with PbSe quantum dots (QDs) were prepared by a conventional melt‐quenching process followed by heat treatment, which exhibit good thermal, chemical, and mechanical stabilities, and are amenable to fiber‐drawing. A broad near infrared (NIR) photoluminescence (PL) emission (1070‐1330 nm) band with large full‐width at half‐maximum (FWHM) values (189‐266 nm) and notable Stokes shift (100‐210 nm) was observed, which depended on the B₂O₃ concentration. The PL lifetime was about 1.42‐2.44 μs, and it showed a clear decrease with increasing the QDs size. The planar [BO₃] triangle units forming the two‐dimensional (2D) glass network structure clearly increased with increasing B₂O₃ concentration, which could accelerate the movement of Pb²⁺ and Se^2? ions and facilitate the growth of PbSe QDs. The tunable broadband NIR PL emission of the PbSe QD‐doped borosilicate glass may find potential application in ultra‐wideband fiber amplifiers.     

Fluorophosphate glasses doped with PbSe quantum dots and their nonlinear optical characteristics

A new fluorophosphate glass matrix containing PbSe quantum dots characterized by a narrow size distribution (ΔR/R ∼ 5–7%, where R is the size of a quantum dot) is prepared under heat treatment. It is demonstrated that fluorophosphate glasses can be doped by introducing (ZnSe + PbO) or PbSe into the composition of the glass. The optical absorption spectra of the quantum dots corresponding to the strong quantum confinement regime are studied over a wide range of quantum-dot sizes (4–18 nm). The nonlinear optical absorption is investigated at a wavelength of 1.54 μm. It is revealed that the introduction of (ZnSe + PbO) rather than of PbSe into the composition of the glass improves the bleaching contrast owing to a more uniform distribution of the quantum dots over the volume of the glass sample.     

Gallium (III) oxide reinforced novel heavy metal oxide (HMO) glasses: A focusing study on synthesis,optical and gamma-ray shielding properties

In this study, three heavy metal oxide glasses (A:46.0PbO-42.0Bi₂O₃-12.0Ga₂O_3, B:45.94PbO-42.66Bi₂O₃-10.0Ga₂O₃-1.4BaO, C:72.8PbO-17.0GeO₂-10.2Ga₂O₃) were synthesized to determine their optical and gamma-ray shielding properties in terms of assessing their potential applications in medical and industrial radiation facilities. Glasses were synthesized using melt quenching method. The optical band gap energy is calculated by the absorption spectrum measured at room temperature. We found a large band at 500 nm that refers to Bi+ions and appears to samples A and B that contain Bi₂O₃ in their compositions. Optical band gap energies were reported as 2.014 ev, 2.055 eV and 2.430 eV for A, B and C samples, respectively. Next, fundamental gamma-ray parameters were also determined using MCNPX general Monte Carlo code and Phy-X/PSD in 0.15–15 MeV photon energy. Our findings clearly showed that the B sample, which includes the highest concentration of Bi₂O₃, has a considerable advantage in terms of gamma-ray attenuation. Moreover, the results also showed that sample B has significantly higher attenuation properties than shielding concretes and several glass shields. It can be concluded that Bi₂O₃ is a useful component for heavy metal oxide glasses in terms of improving gamma-ray shielding capabilities for radiation shielding applications.     

Structural,electrical, and linear/nonlinear optical characteristics of thermally evaporated molybdenum oxide thin films

Homogeneous thin films of Molybdenum oxide (MoO₃) were grown on quartz and glass substrates using the thermal evaporation method. XRD results showed that the MoO₃ powder has a polycrystalline structure with an orthorhombic crystal system whereas the MoO₃ thin films have amorphous nature. SEM images showed that the MoO₃ thin films have a nearly uniform surfaces with worm-like shape grains. The film thickness influences on the linear and nonlinear optical characteristics of MoO₃ thin films that were examined using spectrophotometric measurements and from which, the linear optical constants of the MoO₃ thin films were estimated. The electronic transition type was determined as a direct allowed one. The values of the optical band gap were obtained to be in the range of 3.88–3.72 eV. The dispersion parameters, third-order nonlinear optical susceptibility, and the nonlinear refractive index of the MoO₃ thin films were determined and interpreted in the light of the single oscillator model. The temperature dependence of the DC electrical conductivity and the corresponding conduction mechanism for the MoO₃ films were investigated at temperatures ranging from 303 to 463 K.     

Optical properties of ternary zinc magnesium phosphate glasses

Ternary phosphate glasses of the system (ZnO)₃₀(MgO)_x(P₂O₅)_70−x with x ranging from 5 to 20 mol% were prepared by melt quenching technique. The optical absorption spectra of these glasses were measured at room temperature in the wavelength range between 190 and 1100 nm while the refractive index at wavelength 632.8 nm. The optical absorption indicates that the electronic transition is indirect and associated with phonon-assisted transition. From the absorption spectra, the optical energy band gap (E_opt) and Urbach energy (E_U) values for all the glass samples were calculated from their ultraviolet edges. The values of E_opt is found to increase from 3.36 to 3.44 eV and values of E_U decrease from 0.47 to 0.29 eV with the increase of MgO content. Variation in these optical parameters, density and molar volume is discussed and correlated with the structural changes within the glassy matrix.