Zinc Borate Glasses Research Articles

Modulation instability induced supercontinuum generation in Barium Zinc Borate glass doped with Praseodymium based photonic crystal fiber

Modulation instability induced supercontinuum generation in Barium Zinc Borate glass doped with Praseodymium based photonic crystal fiber

Investigation of electric transport in mixed conducting Na2O modified zinc borate glasses for electrode material using broadband dielectric spectroscopy.

The electrical conductivity of Na2O substituted zinc borate glasses has been studied in the frequency range of 10 mHz to 1MHz and in the temperature range from 313 to 573K. The conduction mechanism has been ascertained using the values of the frequency exponent (s) extracted from the fitting of experimental data of the real part of electric conductivity in light of the Almond-West equation. Depending on the glass composition, the ac conduction in the glasses happened via correlated barrier hopping and non-overlapping small polaron tunneling conduction models. The electric modulus studies support the assertion of composition dependent conduction mechanisms. Furthermore, electronic conduction and ionic conduction have been studied from impedance investigations. Equivalent circuit models were used to fit the Nyquist and Bode plots of each sample at the temperatures under consideration. It has been found that the activation energy values calculated from conductivity, electric modulus, and impedance measurements are more or less the same.

An insight into the transition metal dependent structural, optical, and electrical properties of dysprosium doped lithium zinc borate glasses

A glass series of Dy3+ ions doped zinc vanadium lithium borate with chemical composition xV2O5·(10-x)ZnO·30Li2O·60B2O3 (x = 0, 1, 5, 7, 9, 10) with 1.0 mol% of Dy2O3 has been synthesized by melt quench method. Efforts have been made to identify suitable optoelectronic material by studying the structural, electrical, photo-luminescence (PL), and optical characteristics of the dysprosium ions in the presence of VO2+ ions. PL emission spectra have been explored, depicting that when excited at 386 and 424 nm, the glass matrix is suitable for laser action and at 452 nm, it is apt for cool white light applications.

Noncytotoxic Dy3+ -activated glass emits cool white light for near ultraviolet-based white light-emitting diodes, visible lasers, and biomedical applications.

Using the melt quenching technique, a lithium zinc borate glass (LZB) system with trivalent dysprosium ions (Dy3+ ) was synthesized, and the luminescence and lasing properties of these materials were examined for the generation of white light. Structural investigation through X-ray diffraction revealed that the prepared glass had an amorphous nature. The optimized glass containing 0.5 Dy3+ had a direct optical band gap of 2.782 eV and an indirect optical band gap of 3.110 eV. A strong excitation band at 386 nm (6 H15/2 →4 I13/2 ) was recognized in the ultraviolet (UV) light region of its excitation spectrum. Emission bands could be seen in the photoluminescence spectrum at 659, 573, and 480 nm under the 386 nm excitation. These transitions of emission resembled electronic transitions such as (4 F9/2 →6 H11/2 ), (4 F9/2 →6 H13/2 ), and (4 F9/2 →6 H15/2 ). In a pristine glass matrix, the higher intensity ratio of yellow to blue can result in the production of white light. The optimized Dy3+ ion concentration was observed to be 0.5mol%. In addition, an analysis of lifetime decay was conducted for all synthesized glasses, and their decay trends were systematically investigated. Noticeably, we assessed the photometric parameters and found that they were close to the white light standard. Furthermore, a cytotoxicity study was carried out using lung fibroblast (WI-38) cell lines for the optimized 0.5Dy3+ -doped LZB glass and it appeared to be noncytotoxic. It is clear from the results that the noncytotoxic LZB glass doped with 0.5 Dy3+ ions could be a suggestive choice for the manufacture of white light-emitting diodes and lasers using near-UVs.

Annealing and intensity dependent femtosecond nonlinear optical studies of sodium zinc borate oxide glasses incorporated with gold nanoparticles

Herein, we explored the annealing and intensity–dependent femtosecond (fs) nonlinear optical (NLO) studies on sodium zinc borate (NZB) glasses embedded with gold nanoparticles (NPs). The glasses were prepared by the melt–quench process and subjected for thermal treatment at 450 °C at different schedules in a normal atmosphere. It was identified that the glass annealed for 12 hr (i.e., the NZBAu12 glass) had the maximum saturation intensity and negative nonlinear refraction values. Therefore, the intensity–sensitive NLO investigations then conducted on that glass to understand the influence of intensity of laser radiation on NLO proeprties on gold NPs embedded glasses. The saturable absorption observed at lower intensity was switched to reverse saturable absorption (two–photon absorption) during the exposure with high fluence laser pulses. However, the nonlinear refraction sign was unchanged with increase of intensity of laser radiation. The strategy explored in this work might pave the way for achieving the strong nonlinear traits in borate–based glasses routed with gold NPs. The study outcomes endorse the benefits of NZBAu12 glass for optical switching functionalities under low–intensity pulse excitation, as well as for optical limiting applications under high–intensity pulse excitation.

Impact of ligands on the performance of band-stop and bandpass optical filter of cobalt sodium zinc borate glass

Impact of ligands on the performance of band-stop and bandpass optical filter of cobalt sodium zinc borate glass

Role of silver on the photoluminescence and structural studies of sodium antimony zinc borate glass

Role of silver on the photoluminescence and structural studies of sodium antimony zinc borate glass

Distinctive spectroscopic features of samarium ions in the lithium zinc-borate glass

Inducing the spectral features of samarium ions (Sm3+) in a borate glass host with the required enhancements is the main challenge. Hence, transparent glass materials made of Sm-doped lithium zinc borate with high optical quality are created by the melt-quenching approach. XRD reveals the disordered structure and the amorphous character of the obtained glassy materials. The structural modifications of these glassy materials are observed via FTIR spectroscopy. The incorporation of samarium oxides into the borate glassy system changes the boron coordination from four-to-three. This, in turn, increases non-bridging oxygens (NBO) in the glassy network. The various physical parameters of these glassy materials are evaluated. Moreover, the ligand field characteristics and optical transitions of Sm3+-doped lithium zinc-borate glassy materials are scrutinized. The indirect bandgap energy values of these glass materials decrease with Sm2O3 additions, whereas the Urbach energies increase gradually. The refractive index values of these glasses lie between 1.20 and 1.42. The tunability of the optical spectra of the investigated glass system, afforded via the various contents of Sm3+ ions, allows the absorption edge to be disentangled from the distinguishing optical transitions of Sm3+ ions. Prominent spectroscopic features of the results suggest the Sm-doped borate glass system towards future applications.

Glass transition and crystallization kinetics of lithium modified zinc borate semiconducting glasses by non-isothermal method

Glass transition and crystallization kinetics of lithium-modified zinc borate glasses of the system 20ZnO.xLi2O.(80-x) B2O3 (x = 10, 20, 30 and 40) have been studied using the non-isothermal method of differential scanning calorimetry (DSC). The 20ZnO·10Li2O.70 B2O3 glass composition has the highest thermal stability and the glass-forming tendency among all other glasses. The activation energy associated with crystallization ((210–318) kJ/mol)), glass transition ((464–531) kJ/mol)), Avrami exponent (3) and frequency factor (2.49 × 109–2.32 × 1017) were extracted from the fitting of different theoretical models and the values are in close agreement with each other. The value of the Avrami exponent was found ∼3 thereby indicates the occurrence of volume nucleation with two-dimensional growth in the currently studied glass system. The formation of Pure monoclinic LiZnBO3 crystalline phase is observed in 20ZnO·30Li2O·50B2O3 and 20ZnO·40Li2O·40B2O3 glass compositions which is a potential candidate for electric double-layer capacitance fabrication.

Tri-doped Ln3+ ions in barium zinc borate glasses: Luminescence behavior at room and cryogenic temperatures

The research work carried out in the paper reports on the effect of BaO and tri doped Er3+, Tb3+, and Gd3+ ions on luminescence characteristics in zinc borate glasses. The work emphasizes the effect of BaO on tri-doped lanthanide ions in borate glasses. The addition of 5 mol% BaO content in the glasses shows more non-bridging oxygens and decreases with addition of BaO content (10 mol%). Glasses show emissions at 311 nm, 543 nm, and 1540 nm for Gd3+, Tb3+, and Er3+ ions, respectively. The Judd-Ofelt method was applied to bring out the significance of the oscillator strength of Tb3+ ions. Higher value of Ω2 was observed in the present glasses indicating their rare-earth covalency is more around Tb3+ ions. Low-temperature luminescence studies were studied for the T2 glass sample for Tb3+ ions. Cryogenic temperature luminescence studies were studied to bring out the significance of 5D4 to 7FJ (J = 3, 2, 1, 0) which is not normally visible at room temperature. The energy is transferred from the Gd3+ to the Tb3+ ions by the Gd3+ ions acting as sensitizers, which helps to adjust the excitation wavelength. Yellowish-green-emitting glasses were observed by illuminating UV light and verified as such from the CIE diagram. The prepared glasses are potential candidate for visible-emitting around yellowish-green colour emitting capability and NIR emitting optical devices and broadband amplifier applications.

Supercontinuum generation in antimony zinc borate glasses—A material perspective

Supercontinuum (SC) generation from alkali antimony zinc borate glasses was investigated using a femtosecond laser. The optical bandgap values were determined for all the glass samples. An enhancement in the generated SC is seen from sodium-doped glass although it possesses the least bandgap among the glass samples. The physical parameters of the glasses such as density, molar volume, refractive index, oxide ion polarizability, and optical basicity have been analyzed and discussed. The smaller values of the metallization criterion indicate the tendency of the glass samples to exhibit metallic behavior, which, in turn, affects the non-linear optical properties of the glasses. The shift in the binding energies of metal cations and oxygen anions was observed using XPS analysis, which gives an understanding about the extent of overlapping of valence orbitals in the glass system. The observations from the physical and structural investigations provide an insight into the anomaly in the enhanced SC generation from the low bandgap sodium-doped glass.

Zinc borate glasses: properties, structure and modelling of the composition-dependence of borate speciation.

The short-range order of binary zinc borate glasses, xZnO-(1-x)B2O3, has been quantitatively described as a function of ZnO content over the entire glass forming range for the first time, to the best of our knowledge. Multiple spectroscopic techniques (11B NMR, Raman, infrared) reveal detailed structural information regarding borate speciation and network connectivity, and a new model for quantifying the molar fractions of short-range order units is proposed. A consistent thermal history dependence for the fraction of tetrahedral boron (N4) is well accounted for by the proposed model. The model predicts density within 0.1% of experimental values and N4 to within 1% of NMR values. The intermediate character of four-coordinated zinc in borate glasses of this series is evident by the far infrared profiles and the glass transition temperature behavior, which decreases non-monotonically with increasing ZnO content.

Preparation and characterization of zinc–borate glasses doped with Ag2O

Using the melt quenching approach, glasses having the formula ZnO-B2O3-Ag2O have been created.Utilising the X-ray diffraction technique, the synthesized glass has been described. The Archimedes method was used to compute the densities of these glasses,and the appropriate formula was used to determine the associated molar volume.Absorption spectra were recorded using a UV–visible spectrometer.Tauc's figure has been used to examine the energy band gap.Ag2O concentration-related variations in band gap energy have been discussed.

Cobalt-Doped Zinc-Borate Glasses: Preparation and Spectral Properties

Cobalt-Doped Zinc-Borate Glasses: Preparation and Spectral Properties

Effect of Pr6O11 on improving the Near–Infrared nonlinear optical characteristics of zinc borate glasses

For achieving superior nonlinear optical (NLO) features of glass samples, we have incorporated rare earth oxide (in this case, it is Pr6O11) in the composition. The NLO properties are rare earth ions concentration–dependent and, therefore, it is crucial to examine the concentration impact on the NLO attributes of glasses. The effectiveness of Pr6O11 concentration on NLO characteristics of the borate–based glass specimens in the near–infrared region in the femtosecond regime is being investigated in the current work using the Z–scan method. The two–photon absorption coefficients were almost constant up to 0.5 mol % of Pr6O11 and then showed increased behaviour. The nonlinear index of refraction magnitudes was improved with Pr6O11 content in the glass compositions. However, the optical limiting thresholds were found to be decreased with Pr6O11 quantity in the glass compositions. These increases in NLO features and optical limiting efficiencies are attributed to the non–bridging oxygens, polarizability and molar refractions of the glasses. The outcomes of Z‒scan characterization unveil that the high Pr6O11 glass specimens are favourable for the production of NLO devices and optical limiters to execute the functioning in the near–infrared region.

Multicolor and warm white luminescence from Dy3+/Eu3+ co-activated glasses for indoor and solid-state lighting applications

Multicolor emitting Dy3+/Eu3+ coactivated lithium zinc borate (LZB) glasses were prepared by the melt-quenching method and their structural, vibrational, morphological, and luminescence properties were investigated. Dy3+ glasses exhibited blue, yellow, and red photoluminescence (PL) bands at 481 nm (4F9/2 → 6H15/2), 576 nm (4F9/2 → 6H13/2), and 665 nm (4F9/2 → 6H11/2) under 386 nm excitation. Eu3+ glasses exhibited strong orange and reddish-orange emissions at 589 nm (5D0→7F1) and 612 nm (5D0→7F2) at 393 nm of excitation. 0.5 mol% Dy3+ is codoped with various Eu3+ concentrations and the energy transfer mechanism is analyzed from the spectral overlay of Dy3+ emission and Eu3+ absorption, Dy3+/Eu3+ PL, and decay profiles as well as from energy transfer parameters. Dy3+/Eu3+ codoped glasses stimulated under different excitation wavelengths of Dy3+ (349, 363, and 386 nm) displayed a decline in the intensity of Dy3+ PL bands and a simultaneous rise in Eu3+ PL bands, demonstrating efficient energy transfer from Dy3+: 4F9/2 → Eu3+: 5D0 due to dipole-dipole interaction. The energy transfer process is supported by a decrement in the lifetimes of Dy3+ when co-doped with Eu3+ compared with singly doped Dy3+ones. The color coordinates and corresponding color temperatures were shifted from neutral to a warm white light region depending on the Eu3+ concentration. The aforementioned results demonstrate the importance of the near-ultraviolet-driven LZB: Dy3+/Eu3+ glasses for their potential application in warm white light and multicolor emitting devices.

Cool white light and tunable multicolor emission from Tb3+/Dy3+ co-activated glasses under different excitations for WLEDs

A set of co-doped (Tb3+/Dy3+) lithium zinc borate (LZB) glasses were developed by melt quenching. The structural evaluation was performed for synthesized glassy matrices. The Dy3+ and Tb3+ individually doped glasses exhibit intense yellow and green luminescence bands at 575 nm (4F9/2 → 6H13/2) and 543 nm (5D4→7F5), respectively. The sensitization effect of Dy3+ on Tb3+ was analyzed by increasing the Tb3+ content with respect to the optimum Dy3+ content (0.5 mol%) in Dy3+/Tb3+. The spectral overlay of Dy3+ luminescence and Tb3+ absorption profiles, Dy3+/Tb3+ PL spectra under different excitations 352, 362, 376, and 385 nm, shortening decay lifetimes of Dy3+ in Dy3+/Tb3+ co-activated glasses, energy transfer (ET) parameters, chromaticity coordinates and their corresponding correlated temperatures all help to explain ET from Dy3+ to Tb3+. At 385 nm of Dy3+ excitation, the optimized co-activated (0.5Dy3++1.0Tb3+):LZB glass displays cool white light emission. The non-radiative ET from Dy3+ to Tb3+ is dominated by electric dipole–dipole interaction and its ET efficiency was calculated to be 63%. At the same time, reverse ET from Tb3+ to Dy3+ was also analyzed. The shift in color coordinates from dominant yellow to greenish-yellow, green and white light emission suggests that Dy3+/Tb3+ co-activated LZB glasses can be a potential candidate for UV converted multicolor and white light emitting devices.

Spectroscopic features of Tb3+ doped strontium zinc borate glasses for green laser applications

These days green laser is preferred as a flexible tool for welding direct bonded copper plates used in power electronics to improve electrification of automotive industry. As terbium is known for green emission, Tb3+ doped strontium zinc borate glasses are melt quenched. The broad hump in x-ray diffraction spectra revealed the amorphous nature. Structural modifications and stability of glasses was shown from fourier transform infrared spectra and differential thermal analysis traces. The Judd-Ofelt intensity parameters are calculated to realize the ligand environment among Tb3+ ions in host glass. The Tb3+ concentration dependent fluorescence properties in visible region and the non-radiative decay rates of 5D4→7F5 transition due to resonant energy transfer apart from intensity quenching of 5D3→7F5 transition in green region was studied. A strong peak registered at 542 nm for the transition 5D4→7F5 in the green region of emission spectra under the excitation of 378 nm. The radiative properties for the prominent luminescent transitions 4D5→7FJ (J=6,5,4,3) of Tb3+ ions are measured using Judd-Ofelt parameters. The values σe, βR,η (%), life- time decay and CIE co-ordinates for the transition 5D4→7F5 confirms that this transition is appropriate for potential green laser.

Ionic Conductivity and Dielectric Relaxations in Li+ Ions Doped Zinc Borate Glass System

The main objective of this work is to study the role of Li+ ions in the ionic conduction of the zinc borate glass system. In this paper, ionic conduction and dielectric relaxations of (30-x) Li2O-xLi2SO4−50B2O3−20ZnO (where x = 0, 2.5, 5, 7.5 mole%) glass system, coded as LLBZ1, LLBZ2, LLBZ3, and LLBZ4, have been discussed. We have performed ionic conductivity measurements in the frequency and temperature range of 40 Hz to 10 MHz and 443 K–500 K, respectively. Increase in conductivity is mainly due to the rise in the temperature, which leads to thermal activation and helps the mobile modifier ions to migrate easily by crossing the barrier. Further, studied dielectric relaxation using the scaling behavior in terms of stretched exponent (β). Dielectric loss tangent (tan δ) shows inverse behavior with increasing frequency rates.

Effect of V2O5 and TeO2 substitution on thermal, structural and wettability properties in lead free bismuth zinc borate-based low temperature sealing glass and preparation of glasses in paste form as an engineering practice

The effect of V2O5 and TeO2 addition on thermal, physical and structural properties of bismuth zinc borate glass was investigated by several techniques including differential thermal analysis (DTA), density, dilatometer, hot stage microscopy (HSM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). Wetting behavior of glasses on Al and glass substrates both in oxidizing and reducing atmospheres has been studied, and it was seen that wettability increased in reducing atmosphere. Bismuth zinc borate glass without V2O5 and TeO2 addition on the aluminum substrate showed the highest wettability, and the contact angle decreased with the temperature increase. It was clearly observed that the wettability increased with the oxidation of aluminum substrate prior to treatment. It was also confirmed by SEM-EDS analysis that the undoped glass and the highest TeO2 doped glass presented good wettability on the glass substrates. The selected glass compositions were formed into a paste and viscosity values ​​were followed at certain periods during 28 days as a novel approach. Low temperature bismuth zinc borate glass pastes with polyvinyl butyral (PVB) binder and 80:20 solid/organic vehicle ratio was applied on glass substrates and shear load values were compared. Consistent results with wettability behaviors were obtained.