Doped Glasses Research Articles

The Effect of Na2O/B2O3 Composition Ratio on the Structure and Properties of Cu+ Doped Luminescent Glass

The Effect of Na2O/B2O3 Composition Ratio on the Structure and Properties of Cu+ Doped Luminescent Glass

Self‐reduction triggered color tuning of Eu3+‐doped aluminosilicate glass for solid‐state white illumination

AbstractRare earth‐doped transparent glass, boasting high transmittance and excellent luminescent properties, holds great potential in the field of all‐inorganic solid‐state white illumination. Currently reported single‐structure solid‐state white lighting usually has the problems of low color rendering index (CRI) and high correlated color temperature (CCT) due to the lacking of red light emission. In this work, a novel single‐structure MgO–Al2O3–SiO2–Eu2O3 (MAS: Eu) glass with color tuning was prepared by the simple glass melting process. Interestingly, the prepared Eu3+‐doped aluminosilicate glass possessed a unique capability to achieve color emission under different excitation wavelengths. The reason for this was attributed to the good self‐reduction capability of the MAS glass, which effectively reduced Eu3+ to Eu2+ under an air atmosphere. Meanwhile, only by regulating the Eu3+ doping concentration, the MAS glass also achieved a tunable emission from blue to white to red light under 380 nm excitation. The acquisition of white light was realized through the multispectral emission of blue–green light emitted by Eu2+ and orange–red light emitted by Eu3+. Remarkably, the single‐structure MAS glass doped with 8 wt.% Eu3+ successfully achieved high‐quality white light and high thermal stability, exhibiting a high CRI of 86, a low CCT of 2761 K, good chromaticity parameters of (0.407 and 0.3192), and the emission intensity at 423 K remains above 86.35% that of room temperature. Meanwhile, the doped Eu3+ exceeded 12 wt.%, without any observable concentration quenching. Moreover, the MAS: Eu glass showed a high transmittance of 90 and a moderate thermal conductivity of 1.45 W/mK (epoxy resin ∼0.17 W/mK). These results would dramatically inspire the development of high‐quality solid‐state white lighting applications.

Effect of Li2O on physical, structural, thermal, optical, and electrical properties of mixed alkali borate glasses containing silver nanoparticles

In this work, mixed alkali borate glasses doped with Li2O were prepared with a molar composition of (75-x) B2O3-15Na2O-8CaO-1V2O5-1AgCl-xLi2O; x = 0, 5, 10, 15, and 20 mol% by using traditional melt-quenching process. X-ray diffraction studies confirmed the amorphous nature of the samples. Upon Li2O doping the glass density, measured at ambient temperature, increases from 2.336to 2.518 g/cm3, while molar volume decreases from 29.637 to 24.337 cm3/mol. The direct and indirect band gap energies determined using UV–Visible absorption analysis was in the range 3.000 –3.285 eV and 2.910–3.218 eV respectively. The DTA measurements indicated that with Li2O addition the thermal stability of the glasses has improved. FTIR study revealed the vibrational modes corresponding to the functional groups present in the glasses. The DC conductivity of the samples (measured at 588 K) was found to increase from 2.394 x 10-4 to 3.987 x 10-4 Ω-1m-1with Li2O content. The temperature dependency of DC conductivity followed Mott’s Small Polaron Hopping (SPH) model at high temperature and Variable Range Hopping (VRH) model at low temperatures. The linear fit of the data to the SPH model yielded the activation energy (W) values in the range 0.152 to 0.693 eV, whereas the density of states at Fermi level evaluated by the VRH model was in the order of 1030 eV-1m-3. The improved electrical conductivity of the prepared Li doped glasses together with their good thermal stability and transparency render them as potential candidates for optoelectronics device applications.

Spectroscopic properties of Ce3+ doped silicate glasses for near-UV white LEDs and blue laser applications.

Spectroscopic properties of Ce3+ doped silicate glasses for near-UV white LEDs and blue laser applications.

Preparation and scintillation properties of Eu3+-doped high crystallinity tellurite glass ceramics

In this study, a high-crystallinity glass-ceramic scintillator doped with Eu³⁺ containing Bi₂Te₄O₁₁ nanocrystals was prepared using a traditional melt crystallization method. The optimal heat treatment conditions, phase structure, and luminescent properties of the glass-ceramics were systematically investigated using various characterization techniques, including DSC, XRD, SEM, and spectrophotometry. To achieve glass-ceramic samples with high transmittance and excellent luminescent performance, the optimal heat treatment process was determined to be 500 °C for 10 minutes. The final sample was found to have a density of 5.9 g/cm³ and a crystallinity of 70%. Strong orange-red light emission was exhibited by the glass-ceramic under both 465 nm light and X-ray excitation. The maximum integral X-ray excited luminescence (XEL) intensity was found to reach 20.2% of that of the commercial Bi4Ge3O12 (BGO) scintillation crystal. It is indicated by the research that Eu³⁺-doped high-crystallinity tellurate glass-ceramics are promising candidate materials for scintillators in the field of X-ray detection.

Synthesis and characterization of erbium silica glass and glass-ceramics for potential low-emissivity coating applications

Silica glasses co-doped with varying concentrations of Er3+ (0.8, 1.5, 4, and 8 mol %) were fabricated employing the sol-gel technique. The effects of erbium concentration were evaluated through several characterization techniques, including X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV-visible transmission spectroscopy, and photoluminescence analysis. The incorporation of erbium ions significantly altered the structural, optical, and photoluminescence properties of the doped glasses. XRD analysis revealed the presence of SiO2 in both tetragonal and hexagonal forms, along with Er2SiO5 crystalline phases. SEM images showed irregular rod-shaped structures with agglomeration and micro-flake cubic shapes. FTIR spectroscopy provided insights into the structural characteristics of the materials. Notably, the optical band gap energy of the glassy films increased, accompanied by fluctuating Urbach energy and a slight reduction in the refractive index, attributed to structural changes within the glass network. Photoluminescence spectra indicated strong emissions at 523 and 543 nm, corresponding to the transitions 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2, respectively. Additionally, a notable near-infrared emission at 1532 nm was observed, linked to the transition 4I13/2 → 4I15/2. The color coordinates of the produced glasses were found to be near the green or yellow regions, suggesting potential applications in optical amplifiers, lasers, and low-emissivity coatings.

The effect of Ce3+ ions on the optical, and radiation shielding properties in Ba–Sn borophosphate glass

This study aims to investigate the structural, optical, and mechanical properties of Ce3+ doped Barium Tin Borophosphate glass for potential applications in nuclear radiation shielding. The Ce3+ Doped Barium Tin Borophosphate glass (50B2O3+20 P2O5+10TiO2+6SrCO3+4SnO+ 4BaF2+5BaCO3+1Ce2O3) was produced according to earlier research, melt quenching method. The amorphous nature of Ce3+ Doped Barium Tin Borophosphate glass was verified by powder X-ray diffraction investigation. The Ce3+ Doped Barium Tin Borophosphate glass's functional groups were determined using Fourier transform-RAMAN and Fourier transform infrared spectroscopy. Using Ultraviolet-Visible spectroscopy the Ce3+ Doped Barium Tin Borophosphate glass was examined. These properties included its optical band gap, extinction coefficient, optical conductivity, and refractive index. Using EDAX and SEM analyses, the chemical compositions and surface morphology of the Ce3+ Doped Barium Tin Borophosphate glass were examined. Ce3+ doped barium tin Borophosphate glass was studied in terms of its excitation and emission spectra using the photoluminescence technique. The glass's CIE coordinates were also looked at. Additionally, the mass attenuation coefficient, half-value layer, mean free path, tenth value layer, and EABF were studied concerning the glass's gamma-ray shielding qualities using the Phy-X software.

Performance evaluation of ∼2.1 μm microchip laser operation in Ho3+ doped germanate glass

An in-band pumped continuous wave (CW) ∼2.1 μm microchip laser is presented for the first time based on a short cavity Ho3+ doped germanate glass (GeO2-PbO-Ga2O3–Na2O: GPGN). A 1.94 μm, 5 W Tm3+ fiber laser was employed for the excitation of the Ho3+ ions. A 19% laser slope efficiency was achieved in a simple, unoptimized plane parallel Fabry-Perot cavity configuration. A positive thermal lens was estimated in the laser cavity with a sensitivity factor of S ∼31 m−1W−1 and an optical path distortion value exceeding 6 μm. The laser results along with the analysis of the thermal lens indicate that with improved thermal management and an optimized cavity configuration GPGN is a promising gain medium for microchip laser operation around 2.1 μm.

Transparent and Thermally Stable Rare-Earth-Doped Luminescent Gallate Glass toward Passive Daytime Radiative Cooling Applications.

Currently, the implementation of passive daytime radiative cooling based on zero-energy cooling methodologies primarily focuses on polymers and composite materials, whereas the available literature on all-inorganic materials is relatively few. Here, we present a novel microcrystalline glass material CaGa0.5Al1.5O4 (CGAO), doped with rare-earth elements and prepared by the high-temperature melting method. This material exhibits long-term stability at 200 °C, coupled with an effective infrared radiation cooling function, demonstrating a 4.9 °C temperature reduction at solar noon. The energy transfer and luminescence mechanisms of Tb3+ and Sm3+ doped CGAO glass have been thoroughly investigated, along with thorough assessments of its thermal stability and hardness. The glass exhibits ultrahigh light transmission in the ultraviolet to near-infrared range, with the transmittance reaching 98% in specific spectral bands. Furthermore, it demonstrates superior luminescent thermal stability, retaining 85.6% and 71.2% of its initial luminescence intensity at 423 and 523 K, respectively. The high-temperature resistance and stability and long-term cooling properties render CGAO glass as an optimal candidate for integration into future energy-efficient and sustainable building designs.

A Review of the Physical, Optical and Photoluminescence Properties of Rare Earth Ions Doped Glasses

Doping glasses with rare-earth ions have garnered significant attention among researchers worldwide. This interest stems from the widespread utilization of rare-earth ions to enhance the optical characteristics of host glasses and exploit the unique spectroscopic properties arising from their optical transitions in the intra-4f shell. Thus, this study reviewed the exceptional potential of rare-earth ion-doped glasses (REIs) in various applications such as solid-state lasers, photonic devices, communication optical fibers, and white light emission. Various methods for the fabrication of glass such as direct melt quenching, sol-gel, ion exchange, sputtering and co-doping techniques were reviewed extensively. The Specific focus was on the physical, optical and photoluminescence properties of glasses produced from glass formers co-doped with rare earth ions. The investigation centers on the comprehensive current applicability of REI-doped glasses. The review concludes based on the physical, optical and photoluminescence properties of rare earth ion-doped glasses that they are extremely useful in photonics, lasers, biomedical and optical communication applications.

Ln3+-doped glasses: Advancing molecular logic for integration into photonic and electronic devices

The rapid miniaturization of electronic devices has pushed the limits of conventional silicon-based technologies, creating a pressing need for novel approaches to sustain the exponential growth of computing power. This study explores the innovative application of Ln3+-doped glasses in developing molecular logic systems as a potential solution. Exploiting Eu3+ and Dy3+, we investigated the luminescence properties under various physical stimuli such as excitation wavelength and temperature. Our findings reveal the capability to construct logic elements of varying complexity, from simple AND and OR gates to advanced FULL-ADDER and FULL-SUBTRACTOR circuits. This work represents the first instance of using Ln3+ exclusively for molecular logic via physical stimuli. The robust and stable optical properties of the doped glasses enable their integration into conventional electronic and photonic devices, potentially revolutionizing the landscape of molecular logic and computing. This research not only enhances the understanding of light-matter interactions in Ln3+-doped systems but also opens new pathways for the development of miniaturized, high-performance innovative computational devices.

Advancing understanding of composition–structure–luminescent properties in laser glass through machine learnings

AbstractRare‐earth (RE)‐doped laser glasses meet urgent needs in national security and scientific fields, and their optimization has garnered extensive attention. However, the design of these laser glasses often relies excessively on trial‐and‐error experimentation, leading to significant costs and a lack of scientific guidance. Herein, we propose an integrated method that combines structural descriptors determined from molecular dynamics simulations, a self‐constructed luminescent database, and a machine learning algorithm to establish the composition–structure–luminescent property (CSLP) relationship. Using an Nd3+‐doped commercial silicate laser glass system as an example, the effectiveness of this approach has been demonstrated. The developed CSLP model enables highly accurate predictions of spectral properties, achieving a determination coefficient (R2) greater than 0.94, based on eight structural descriptors. The importance of different structural descriptors on spectral characteristics is ranked and thoroughly discussed, revealing an intrinsic relationship between the first and second coordination shells around RE ions and luminescent behaviors. Furthermore, the generic structural descriptors identified in the CSLP model can be extrapolated to other systems involving different network formers (e.g., silicate and phosphate) and modifier cations (e.g., Li, Na, K, Ba, and Ca). This capability facilitates the design of laser glasses tailored to specific targets, such as large emission cross‐sections, extended lifetimes, or reduced quenching effects.

Elevating Red Emission: Yb3+ Doped CsPbBr1I2 Nanocrystal Glass for Exceptional PLQY and Stability in Wide Color Gamut Backlit Displays

As display technologies progress towards enhanced visual performance, there was a growing demand for color conversion materials to meet increasingly stringent performance requirements. In recent years, all-inorganic perovskite CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) had gained attention in the field of wide color gamut backlight displays due to their tunable full spectrum, narrow-band emission, high color purity, and ease of processing. However, red-emitting perovskite NCs were still facing challenges with photoluminescence quantum yield (PLQY) and stability. In this study, Yb3+ doped CsPbBr1I2 perovskite nanocrystal glass (Yb3+@CsPbBr1I2 PNG) was synthesized using a melt-quenching technique. Samples emitting at a narrow band centered at 630nm, with a full width at half maximum(FWHM) of 31.8nm, exhibited a high PLQY of 80.36% and retained fluorescence intensity at 98.2% of the initial value in water, maintaining to 92.6% after continuous blue light irradiation for 60 days. Moreover, the optical conversion film Yb3+@CsPbBr1I2@CsPbBr3@PET developed in our study showcased color gamut coverage surpassing 132.9% of the NTSC 1953 standard and 98.8% of the Rec.2020 standard. In summary, the highly efficient and remarkably stable red-emitting Yb3+@CsPbBr1I2 PNG composite material introduced in this study paved the way for future advancements in wide color gamut and ultra-high definition backlight display technologies.

Spectral and Luminescence Study of Er3+ Doped Phosphate Glasses for the Development of 1.5 µm Broadband Amplifier

Ytterbium zinc lithium lead alumino antimony borophosphate glasses containing Er3+ in (25-x)P2O5: 10ZnO: 10Li2O: 10PbO: 10Al2O3: 10Sb2O3: 10Y2O3: 15B2O3: Er2O3 (where x=1, 1.5,2 mol %) have been prepared by melt-quenching method. The amorphous nature of the glasses was confirmed by x-ray diffraction studies. Optical absorption, excitation Spectrum and fluorescence spectra were recorded at room temperature for all glass samples. Judd-Ofelt intensity parameters Ωλ (λ=2, 4, 6) are evaluated from the intensities of various absorption bands of optical absorption spectra. Using these intensity parameters various radiative properties like spontaneous emission probability, branching ratio, radiative life time and stimulated emission cross– section of various emission lines have been evaluated.

Influence of transition metals on the radiation shielding capability of Eu3+ ions doped telluro borophosphate glasses

The present investigation is focused on the synthesis and analyses of Eu3+ doped strontium telluro borophosphate glasses for effective shielding. Out of the prepared glasses, Nb added glass shows a closely packed structure with higher elastic moduli suggesting that it can withstand longitudinal stress. The average coordination number values decline with the structural modification from 4.319 to 3.737 which explains BOs being created in the solid system. The MC simulation code estimates the attenuation coefficient for the samples and illustrates certain metal oxides' behaviour in enhancing the radiation shielding properties of the fabricated glasses. This investigation shows Nb2O5 containing glasses have the best impact on the fabricated glasses' radiation shielding properties, where the produced glasses’ LAC was in the 29.609–0.193 cm−1 range. Also, a thickness of 3 cm from the aforementioned glass has the ability to attenuate over 62.5 %, and 43.9 of the emitted photons with Eγ values of 0.867 MeV and 2.506 MeV, respectively. On the other hand, the metal oxide with the lowest shielding enhancement is ZnO, where its LAC reduced from 22.896 to 0.176 cm−1 with a γ-photon energy increase of 0.01 and 2.506 MeV, respectively.

Enhanced scintillating performance in Tb3+ doped oxyfluoride glass for high-resolution X-ray imaging

Scintillators that exhibit excellent scintillation performance coupled with superior radiation resistance are anticipated to cater the growing demand of X-ray detection across various fields including medicine and scientific research. Oxyfluoride glasses, which combine the benefits of both fluorine and oxide glasses, show significant potential as scintillator candidates. Here, highly transparent Tb3+ doped oxyfluoride glasses with splendid radioluminescence were successfully synthesized by melt quenching method with the aid of a two-step component tuning strategy. The luminescence excited by X-ray and ultraviolet light are significantly enhanced by boosting the effective atomic number of glass components and optimizing the B2O3/Al2O3 ratio. The integrated X-ray excited luminescence intensity of representative specimen reaches 219% of that of BGO. Exceptional anti-irradiation recoverability and thermal stability of 93% @ 573 K are conferred in the resultant glass. Moreover, X-ray imaging with a spatial resolution of up to 20 lp mm−1 was triumphantly achieved. These properties testify that the prepared oxyfluoride glass owns an enormous application foreground in X-ray imaging.

Tunable broadband luminescence of the novel Sn2+ doped oxyfluoride glass and glass-ceramics for W-LEDs

The demand for white-light luminescent materials for the white-light-emitting diodes (W-LEDs) field has been growing in modern life. In this work, a series of Sn2+ and Mn2+ ions co-doped highly transparent white-light emitting oxyfluoride glasses (precursor glass, PG) and Sr2LuF7 glass-ceramics (GC) were successfully prepared by the melt-quenching technique. Their luminescent and structural properties were investigated by the transmission spectra, excitation and emission spectra at different temperatures (300-500 K), luminescent decay curves, XRD, and TEM characterizations. Upon excitation with ultraviolet (UV) light, tunable broadband blue-white light emissions of Sn2+ were obtained by adjusting the concentration of Sn2+ ions. A conspicuous energy transfer process from Sn2+ to Mn2+ was observed in Sn2+/Mn2+ co-doped samples. Tunable broadband luminescence between blue-white light and orange-red light regions and nearly pink-white light emission was realized by varying Mn2+ concentration. Furthermore, compared to PG samples, the emissions were enhanced in GC samples due to the crystallization of Sr2LuF7 nanocrystals. Excellent thermal stability was also performed in these Sn2+ doped PG and GC samples with a recovering value of 96 % and 98.8 %, respectively. Simultaneously, Sn2+ doped PG and GC samples also own good optical thermal sensitivities with an SA value of 2.28 % and 2.47 % K-1, respectively. Our results indicate that these Sn2+/Mn2+ co-doped PG and GC may serve as tunable light sources under UV excitation and have prospects on the ratiometric optical thermometry fields.

Temperature-dependent electrical investigations and explication of the equivalent operational Warburg impedance by Bode and Nyquist plots of Yb3+ doped silicate glass

Multi-component silicate glass doped with Yb3+ and synthesized by the sol–gel technique was subjected to broadband dielectric spectroscopy to determine the energy storage and electrode functionalities. Raman spectroscopy confirms the existence of the silicate and phosphate tetrahedra, with the structural alterations by the non-bridging oxygens to form a compact glass network. Bode and Nyquist impedance plots suggest the suitability of the glass as electrodes, whose functionality is simulated to a circuitry constituting two parallel combinations of a resistor and constant phase element each, and in series with Warburg diffusion impedance element (W). The glass evinces a high conductivity and corrosion resistance, suggestive of electrodes in batteries for energy storage. The inception of W on the low-frequency domain indicates significant space charge polarization, and augmented dielectric constants. The capacitance of 0.9 nF at 100 Hz demonstrates its potentiality for multi-layer dielectric substrates in radio frequency capacitors to enhance electrical energy storage.

CsPb(Br/Cl)3-Sm3+ codoped glasses for optical temperature sensing in FIR and chromatic coordinate modes

We have fabricated Sm3+ doped glasses, CsPb(Br/Cl)3 quantum dots (QDs) glasses and CsPb(Br/Cl)3-Sm3+ codoped glasses by melt-quenching and subsequent heat treatment for optical temperature sensing. Photoluminescence (PL), photoluminescence excitation (PLE) spectra and PL decay have been measured. Two CsPb(Br/Cl)3-Sm3+ samples with different PL peaks of QDs at 486 nm and 503 nm have been studied for fluorescence intensity ratio (FIR) and chromatic coordinate sensing. The CsPb(Br/Cl)3 QDs and Sm3+ ions exhibit distinguished spectral components and they are dynamically independent. PL intensity of QDs rapidly decreases with temperature, whereas PL intensity of Sm3+ slowly decreases with temperature. PL intensity of Sm3+ ions and CsPb(Cl/Br)3 QDs have been independently fitted. Then, FIR sensing has been studied. The different variation in PL intensity with temperature for Sm3+ and CsPb(Cl/Br)3 leads to the change of luminescent color and chromatic coordinate. The chromatic coordinate sensing has also been studied. Absolute sensitivity (Sa) and relative sensitivity (Sr) have been analyzed for both FIR and chromatic coordinate sensing. Compared with the chromatic coordinate mode, FIR mode has the larger Sa and Sr. But the chromatic coordinate method is more convenient for application, which does not require separating two spectral components. Both FIR and chromatic coordinate sensing modes show outstanding temperature cycling characteristics.

Investigation of structural, optical characteristics of Gd3+ doped phosphate glass for radiation shielding applications

Gadolinium doped phosphate glass was created with a composition of 70 P2O5 + 5Al2O3 + 5 Ba2CO3 + 9 KF2 + 5 MnO2 + 5 SnO+1 Gd2O3 by using the melt-quenching process. The prepared glass sample’s amorphous nature was confirmed by the X-ray diffraction analysis. FT-IR examination confirms the presence of phosphate functional groups. Glass’s optical band gap was found to be 3.5 eV using Tauc’s plot method. The photoluminescence analysis indicates that the emission band at around 311 nm. The Commission International de I’Eclairage (CIE) was employed. It was identified that the computed chromaticity coordinate values (x = 0.3164 and y = 0.3371) were situated in the summer sunlight zone, close to the white light region. The attenuation capabilities of the gadolinium-doped phosphate glass sample were validated by the gamma ray shielding parameters. The mass attenuation coefficient and Mean free path of the prepared glass were fund to be 4.41 × 105 cm2/g at 0.015 MeV and 12.4 cm at 15 MeV respectively. In terms of infiltration deepness up to 40 MFP, the energy-related energy buildup factor (EBF) and energy absorption buildup factor (EABF) of glasses were calculated using the five (a, b, c, d, and Xk) parameters of the G-P fitting scheme. All of the results show that the synthetic glass can be used as shielding materials against gamma radiation.