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• First TL investigation on Sm3+-Er3+ and Sm3+-Yb3+ co-doped BaO-ZnO-LiF-B 2 O 3 glass. • Sm3+-Er3+ and Sm3+-Yb3+ are activator-quencher combinations for TL intensity. • Anomalous loss of signal of Sm3+ doped glass countered by doping Er3+ and Yb3+. • TL dosimetry performance can be tuned by the doping/co-doping of rare-earth ions. The consequences of doping Er3+ and Yb3+ ions on the thermoluminescence (TL) dosimetry performance of the BaO-ZnO-LiF-B 2 O 3 -Sm 2 O 3 glass system were examined for the first time. The incorporation of Er3+ and Yb3+ ions were found to be highly detrimental to the TL intensity, sensitivity, and trap density of the Sm3+ doped glass. Although Sm3+ ions enhanced the integrated TL intensity of the host glass by two thousand times, Sm3+-Er3+ and Sm3+-Yb3+ combinations functioned like activator-quencher systems. Contrary, the problem of anomalous loss of 50% signal after a storage week of the Sm3+ doped glass was effectively countered by doping Er3+ (2% loss) and Yb3+ (8% loss) ions. From the trap parameters, the elimination of some shallow traps and deepening of some existing ones was reasoned for minimizing fading. Even if the Er3+ and Yb3+ ions adversely affected the TL intensity of the Sm3+ glass, they greatly improved the stability. The observations indicate that the TL dosimetry performance of a glass system can be suitably tuned by the doping/co-doping of rare-earth ions. [ABSTRACT FROM AUTHOR]

The present paper explores the thermoluminescence characteristics of Ca 2 Al 2 SiO 7 :Dy3+ phosphors prepared via combustion method. The studies concentrate on the application of samples prepared for dosimetry applications. XRD, scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), and Fourier transform Infrared spectroscopy (FTIR) analysis were conducted to get the structural, morphological, and elemental composition of prepared samples. Photoluminescence (PL) studies were performed to study the luminescence properties of Ca 2 Al 2 SiO 7 :Dy3+ samples. Under 350 nm excitation, major peaks at 478 nm (blue), 578 nm (yellow), and 663 nm (red) were found in emission spectra. The correlated color temperature (CCT) value is within the range 5400 K–6400 K which corresponds to cool white light emission. Thermoluminescence studies were conducted after the irradiation of phosphors with γ doses from 50 Gy to 5 kGy. The glow curves were deconvoluted and the kinetic parameters were calculated. And the linear dose response from 100 Gy to 3 kGy doses suggests the suitability of Ca 2 Al 2 SiO 7 :Dy3+ phosphors in high dosimetry applications. [Display omitted] • Ca 2 Al 2 SiO 7 :Dy3+ phosphors prepared via combustion method. • CCT value is within the range 5400 K–6400 K. • Thermoluminescence linear dose response at high doses. [ABSTRACT FROM AUTHOR]

• Effect of Eu2O3 on PL properties was investigated and confirmed the optimize concentration. • Efficacy of Ag NPs on PL properties of optimized Eu2O3 activated glasses were investigated. • Role of Ag NPs on enhancing the PL properties has been underlined. • The 0.6 mol% of AgNO3 embedded glasses were beneficial for the optoelectronic devices. Efficacy of silver nanoparticles on photoluminescence properties on optimized Eu 2 O 3 doped borate glasses has been studied and discussed in detail. The presence of homogeneously distributed and spherically shaped Ag nanoparticles was confirmed by electron microscopic images. With increase of AgNO 3 concentration the photoluminescence intensity of Eu3+ transitions improved up to 0.6 mol% and subsequently quenched at 0.8 mol% of AgNO 3. The enhancement in photoluminescence properties observed as the AgNO 3 concentration raised to higher level was ascribed to local field effect and transmit of energy from Ag nanoparticles to the tri–positive europium ions. While the reduction in photoluminescence properties at higher doping level of AgNO 3 was attributed to reverse transmit of energy from tri–valent europium ions to Ag nanoparticles. Other mechanisms liable for the attenuation in photoluminescence properties are also highlighted. The energy transfer from Eu3+ ions to Ag0 nanoparticles was responsible for the reduction in radiative lifetime magnitudes. The studies suggest the glass sample containing 0.6 mol% of AgNO 3 (i.e. SNBEuAg0.6) beneficial for optoelectronic and photonic applications. [ABSTRACT FROM AUTHOR]

Efficacy of silver nanoparticles on tuning the optical nonlinear characteristics of Sm3+ doped borate‒based glasses has been investigated comprehensively and the outcomes are provided. The nonlinear optical (NLO) attributes were retrieved using the Z‒scan technique under an ultrafast pulse excitation with the wavelength ranging from 700 nm to 1000 nm. Reverse saturable absorption (RSA), ascribed to two‒photon absorption, was realized in open aperture Z‒scan profiles whereas refraction nonlinearity of positive type due to the self‒focusing was observed in closed aperture Z‒scan data. Based on the Z‒scan results along with the figure of merit condition (higher than unity), it was identified that the silver nanoparticles embedded Sm3+ containing glass hosts are competing materials for NLO device applications to function in near‒infrared region. • Influence of silver NPs content on NLO features of Sm3+ ions routed glasses has been studied. • Ultrafast NLO properties were investigated in the region of 700–1000 nm. • The NLO features were enhanced with increase of Ag NPs concentration. • The results revealed Ag NPs embedded glasses are competing materials for NLO devices. [ABSTRACT FROM AUTHOR]

The present work focuses on Dy3+ doped 20SiO 2 -(20-x) B 2 O 3 –10Al 2 O 3 –10ZnO–30NaF–10ZnF 2 glass ceramics (GCs), a white light emitting material prepared by conventional melt-quenching technique and thermal treatment. The glass ceramics exhibited good morphological evolution of α-Na 3 AlF 6 crystals at elevated temperatures. Bandgap values are obtained lower for glass ceramics compared to precursor glass which almost tends to come closer to the bandgap value of semiconductor. A good photoluminescence (PL) performance is monitored in glass ceramics with increased emission intensity having two dominant peaks at 482 and 575 nm. Stimulated emission cross section in glass ceramics obtained higher for the level 6H 13/2 characterize their significance in laser active media. Quantum efficiency is achieved greater than 80% for glass ceramics ensures their appropriateness for LEDs application. In particular, the yellow to blue intensity, colour coordinates and colour correlated temperature have been evaluated for glass ceramics. With the formation of α-Na 3 AlF 6 crystalline phase surrounded by Dy3+ ions, the PL properties in glass ceramics is enhanced notably. The obtained glass ceramics should be acknowledged as a promising material in white-LEDs and optoelectronic devices applications. [Display omitted] • Glass ceramics containing α-Na 3 AlF 6 crystalline phase is obtained through different annealing temperatures. • Morphological analysis shows the evolution of small crystals in the glass ceramics. • Judd-Ofelt calculation reveals the covalency character of both glass and glass ceramics. • Emission intensity and quantum efficiency of glass ceramics is improved with formation of α-Na 3 AlF 6 crystalline phase. • The prepared glass ceramics showed bright white light emissions. [ABSTRACT FROM AUTHOR]

The 10BaO–20ZnO–20LiF-(50- x)B 2 O 3 - x Er 2 O 3 (x = 0, 0.1, 0.5, 0.7, and 1.0 mol %) glass system was studied for green emission device, NIR laser, and optical amplifier applications. The impact of Er3+ doping was assessed through structural, optical, and thermal properties. The Er3+ ions behaved as network modifiers and decreased the network rigidity by the transformation of [BO 4 ] → [BO 3 ] and Non-Bridging Oxygens. This was consistent with the decrease in the glass transition temperature. Ten absorption peaks of Er3+ ion equivalent to transitions from 4I 15/2 to various excited levels were quantified through their oscillator strengths. Through broadband impedance spectroscopy, the insulating property of the glass system was authenticated by the persistence of dc-conductivity in the order of 10−10 Scm−1 up to 523 K. With 378 nm excitation, a violet emission (2H 9/2 → 4I 15/2) and two intense green emissions (2H 11/2 → 4I 15/2 , 4S 3/2 → 4I 15/2) were noticed. The NIR emission (4I 13/2 → 4I 15/2) was observed at 1531 nm with 378 and 980 nm excitations and the corresponding decay curves were recorded. The Inokuti-Hirayama model indicated the increase in the energy transfer and reduction in critical distance amid the Er3+ ions with doping leading to energy migration through cross-relaxations and lifetime quenching. The laser parameters were determined from Fuchtbauer-Ladenburg theory. The color coordinates of the samples were lying in the green region, with purity >89% and CCT >6000 K. The gain coefficient from McCumber theory was positive for a population inversion >50%, with a wide gain between 1460 and 1565 nm, extending the application of the glass system as an optical amplifier in the S + C communication window. [Display omitted] • Spectroscopic study of BaO–ZnO–LiF–B 2 O 3 –Er 2 O 3 glass system. • Good thermal stability for optical fiber-drawing. • CIE coordinates in green region, color purity >89%, and CCT >6000 K. • NIR emission (4I 13/2 → 4I 15/2) at 1531 nm, decay time 0.57–0.37 ms with Er 2 O 3 doping. • Wide gain in the S + C communication window for optical amplifier application. [ABSTRACT FROM AUTHOR]

We report for the first time the Thermoluminescence (TL) enhancement of intensity, stability, and sensitivity of a novel Yb3+ doped BaO–ZnO–LiF–B 2 O 3 glass host by Sm3+ co-doping. The optimum co-doping of Sm3+ ions to the Yb3+ optimum doped glass intensified the TL counts by 6 times and that of the undoped glass by 157 times. This was reasoned to the increment in the trap density. The kinetic parameters signified the restructuring role of Sm3+ ions by creating deeper traps with higher lifetimes and activation energies. This was beneficial in enhancing the stability of the Yb3+ doped glass by minimizing the thermal fading after a week from 42% to 10%. The co-doping also enhanced the sensitivity and lowered the threshold dose. The results present the perspective of Sm3+ ions as TL activators. The TL dosimeter characteristics of the co-doped glass were favorable for its potential application in γ-environment (0.25–1 kGy) and food irradiation. ZLBBY0.1 glass: 10BaO–20ZnO–20LiF-49.9B 2 O 3 -0.1Yb 2 O 3 ZLBBY0.1S0.5 glass: 10BaO–20ZnO–20LiF-49.4B 2 O 3 -0.1Yb 2 O 3 -0.5Sm 2 O 3. [Display omitted] • γ-TLD characteristics of BaO–ZnO–LiF–B 2 O 3 –Yb 2 O 3 –Sm 2 O 3 glass system examined • Augmentation of TL intensity of base glass after Yb3+-Sm3+ co-doping • TL sensitivity and stability of co-doped glass better than Yb3+ mono-doped glass • TLD characteristics appropriate for food irradiation application [ABSTRACT FROM AUTHOR]

In present work we report the thermal, structural and optical behaviour of 20SiO 2 -(20-x) B 2 O 3 –10Al 2 O 3 –10ZnO–30NaF–10ZnF 2 -xEu 2 O 3 glass system where Eu 2 O 3 ions is doped in different molar concentrations (x = 0.1, 0.5, 1.0, 1.5, 2.0 and 2.5 mol %). The Differential thermal analysis measurement was employed to study the thermal stability of the glasses through various thermal parameters such as Dietzel factor (Δ T) , Hruby's parameter (K H) , Weinberg Parameter (K W) and Lu and Liu Parameter (K L L). FTIR studies exhibit the presence of BO 3 , BO 4 , SiO 2 vibrational units and the deconvoluted peak areas is used for the calculation of bridging and non-bridging oxygens. From the absorption spectra, the indirect bandgap energy (E g) and Urbach's energy (E U) of the glasses have been calculated. Judd-Ofelt (JO) intensity parameters (Ω 2 and Ω 6) have been evaluated from the emission spectrum. The radiative parameters such as radiative transition probability (A R), branching ratio (β R), stimulated emission cross-section (σ se) and radiative lifetimes (τ R) were obtained using the JO parameters for the transitions 5D 0 →7F 1,2,4 of Eu3+ ions. The decay life time of the 5D 0 level is found to be single-exponential for all the Eu3+ doped glasses. An increase in lifetime values for the prepared glasses was found with increase in Eu3+ concentration from 0.1 mol% to 2.0 mol%. The colour chromaticity values and CCT values show the bright red emission from the prepared glasses. [Display omitted] • Eu3+ doped Zinc Alumino Boro-Silicate glasses are prepared by melt-quenching technique. • Thermal stability of the glasses was studied analyzed with different thermal parameters. • Judd-Ofelt parameters calculated from the emission spectra reveal the covalency character of Eu3+ ions. • Radiative parameters show improved stimulated emission cross-section (σse) for ZABSEu2.0 glass. • The prepared glasses showed bright red light emissions. [ABSTRACT FROM AUTHOR]

The development of active electrocatalysts and photocatalysts for hydrogen evolution reaction (HER) and for environmental remediation is a huge challenge. Research is still underway on the development of low-cost catalytic materials with appreciable efficiency for HER. In the present study, a composite of metal organic framework (MOF) with CdS and graphene (NH 2 -MIL-125(Ti)/CdS-graphene) composites were developed with different loadings of graphene material via solvothermal technique. Further the electrocatalytic activity of the synthesized catalysts were investigated for HER and photocatalytic degradation of dye. Results show that the synthesized catalyst with a less amount of graphene was more active. HER results showed a less Tafel slope of 70.8 and 61.9 mVdec−1 with 15.6 mA/cm2 and 15.46 mA/cm2 current densities under light on and off conditions. Further the dye degradation activity of the synthesized catalysts was tested with Rhodamine B dye and results showed that the catalyst showed excellent activity for low weight loading of graphene with a degradation efficiency of 95 % and followed pseudo first order kinetic model. Overall results showed that the synthesized composites are promising for HER and photocatalytic applications. • NCG 5 wt% served as good electrodes for HER with 141.19 mV overpotential compared to other Composites. • NCG 5 wt% Showed an exchange current density of 15.46 mA/Cm2 and a Tafel slope 61.9 mV/dec in alkaline medium. • The reaction follows Volmer- Heyrovsky reaction mechanism. [ABSTRACT FROM AUTHOR]

10BaO–20ZnO–20LiF-(50- x)B 2 O 3 - x Sm 2 O 3 (x = 0, 0.1, 0.3, 0.5, 0.7, and 1.0 mol %) glasses were synthesized with an objective to examine the γ-radiation-induced defects and Thermoluminescence (TL) characteristics towards potential TL dosimetry application. The addition of 0.1 mol % Sm 2 O 3 to the host glass led to a drastic enhancement (almost two thousand times) in the TL intensity and concentration quenching was seen thereafter. The Sm 2 O 3 concentration and γ-dose for the examination of defects and TL features were optimized to be 0.1 mol % and 3 kGy, respectively. The lack of distinct peaks in the X-Ray Diffraction pattern confirmed the glass amorphous nature. The structural modification after irradiation was conveyed in the optical absorption spectroscopy by the presence of color centers and in Fourier Transform Infrared spectroscopy by the increase in the Non-Bridging Oxygens. The color centers were identified as Non-Bridging Oxygen Hole Center and Boron E ' -center from the Electron Spin Resonance characterization. The glass manifested a good linear TL response between 0.25 and 3 kGy, high sensitivity, a minimum detection dose of 2 ± 0.2 Gy, reusability and reproducibility after annealing at 523 K for 15 min, Z e f f of 9.6, and trap activation energies between 0.47 and 1.28 eV. The application of the titled glass system as a potential TL dosimeter is proposed for food irradiation, and γ-environment (up to 3 kGy). [Display omitted] • Sm 2 O 3 doped BaO–ZnO–LiF–B 2 O 3 glass system investigated for γ-TLD characteristics. • Two thousand times enhancement in TL intensity after 0.1 mol % Sm 2 O 3 incorporation. • TL characteristics suitable for high-dose γ-dosimetry (0.25–3 kGy). • Color centers post-irradiation evaluated through optical and structural properties. [ABSTRACT FROM AUTHOR]

We developed new composites for photons shielding applications. The composite were prepared with epoxy resin, red clay and bismuth oxide nanoparticles (Bi 2 O 3 NPs). In order to establish which ratio of red clay to Bi 2 O 3 NPs provides the best shielding capabilities, several different ratios of red clay to Bi 2 O 3 NPs were tested. The transmission factor (TF) was calculated for two different thicknesses of each sample. From the TF data, we found that epoxy resin materials have a high attenuation capacity at low energy. For ERB-10 sample (40%Epoxy + 50% Red clay + 10% Bi 2 O 3 NPs), the TF values are 52.3% and 14.3% for thicknesses of 0.5 and 1.5 cm (at 0.06 MeV). The composite which contains the maximum amount of Bi 2 O 3 nanoparticles (40%Epoxy + 50% Red clay + 10% Bi 2 O 3 NPs, coded as ERB-30) has lower TF than the other composites. The TF data demonstrated that ERB-30 is capable of producing more effective attenuation from gamma rays. We also determined the linear attenuation coefficient (LAC) for the prepared composites and we found that the LAC increases for a given energy in proportion to the Bi 2 O 3 NPs ratio. For the ERB-0 (free Bi 2 O 3 NPs), the LAC at 0.662 MeV is 0.143 cm -1 , and it increases to 0.805 cm -1 when 10% of Bi 2 O 3 NPs is added to the epoxy resin composite. The half value layer (HVL) results showed that the thickness necessary to shield that photons to its half intensity can be significantly lowered by increasing the weight fraction of the Bi 2 O 3 NPs in the epoxy resin composite from 0 to 30%. The HVL for ERB-20 and ERB-30 were compared with other materials such as (Epoxy as a matrix material and Al 2 O 3 , Fe 2 O 3 , MgO and ZrO 2 as filler oxides in the matrix at 0.662 MeV. The HVL values for ERB-20 and ERB-30 are 4.385 and 3.988 cm and this is lower than all the selected epoxy polymers., (© 2023. The Author(s).)

The crystal structure and magnetic state of the (1 − x)BiFeO3-(x)BiMnO3 solid solution has been analyzed by X-ray diffraction using lab-based and synchrotron radiation facilities, magnetization measurements, differential thermal analysis, and differential scanning calorimetry. Dopant concentration increases lead to the room-temperature structural transitions from the polar-active rhombohedral phase to the antipolar orthorhombic phase, and then to the monoclinic phase accompanied by the formation of two-phase regions consisting of the adjacent structural phases in the concentration ranges 0.25 < x1 < 0.30 and 0.50 ≤ x2 < 0.65, respectively. The accompanied changes in the magnetic structure refer to the magnetic transitions from the modulated antiferromagnetic structure to the non-colinear antiferromagnetic structure, and then to the orbitally ordered ferromagnetic structure. The compounds with a two-phase structural state at room temperature are characterized by irreversible temperature-driven structural transitions, which favor the stabilization of high-temperature structural phases. The magnetic structure of the compounds also exhibits an irreversible temperature-induced transition, resulting in an increase of the contribution from the magnetic phase associated with the high-temperature structural phase. The relationship between the structural parameters and the magnetic state of the compounds with a metastable structure is studied and discussed depending on the chemical composition and heating prehistory.

Strong nonlinear absorption (NLA), reduced optical limiting (OL) thresholds, and high radiation shielding parameters are required for the effective use of glasses in the laser radiation and nuclear radiation protecting materials. In view of this, the efficacy of Sm 2 O 3 on the nonlinear optical (NLO) and OL properties were ascertained (at 532 nm) along with radiation shielding characteristics. The open and closed aperture Z-scan profiles revealed the presence of positive NLA and nonlinear refraction (NLR) phenomena respectively. OL measurements showed the existence of limiting behavior in the studied glasses. The NLA and NLR coefficients were improved while the OL thresholds were decreased as the doping of Sm 2 O 3 elevated to a higher doping level. These improvements in NLA, NLR coefficients and OL efficiencies were attributed to the non-bridging oxygens and high polarizable Sm 3+ ions. The NLA and OL results clearly suggest the high (5 mol %) Sm 2 O 3 doped glass (Sm5CNLB) glass is beneficial to protect the delicate devices and human eye by suppressing the high energy laser light. The theoretical linear attenuation coefficients (LAC) values of the presented Sm x CNLB glasses were obtained with the help of Phy-X software between 0.284 and 1.333 MeV. At 0.284 MeV, the maximum values occur and take values between 0.302 (for Sm0CNLB) and 0.409 cm -1 (for Sm5CNLB). We found that the LAC for the presented Sm x CNLB glasses is a function of Sm 2 O 3 content, where the LAC tends to increase, corresponding to the high probabilities of interaction, as the content of Sm 2 O 3 changes from 0 to 5 mol %. The effective atomic number (Z eff ) for the presented Sm x CNLB glasses was examined between 0.284 and 1.333 MeV. As the amount of Sm 2 O 3 is added, the Z eff increases, and this was observed at any energy.

The radiation shielding features of the ternary oxyfluoride tellurite glasses were studied by calculating different shielding factors. The effect of the TeO 2 , WO 3, and ZnF 2 on the tested glass system's attenuating performance was predicted from the examination. The mass attenuation coefficient (µ/ρ) values for the oxyfluoride tellurite glasses depend highly on the concentration of WO 3, as well as ZnF 2 . All the present ZnFWTe1-ZnFWTe5 samples have higher µ/ρ values than that of the pure TeO 2 glass at all energies. For the samples with a fixed content of WO 3 , the replacement of TeO 2 by ZnF 2 increases the µ/ρ, while for the glasses with a fixed content of TeO 2 , the replacement of WO 3 by ZnF 2 results in a decline in the µ/ρ values. The results revealed that ZnFWTe4 has the lowest linear attenuation coefficient (µ) among the oxyfluoride tellurite glasses, whereby it has a slightly higher value than pure TeO 2 glass. The maximum effective atomic number (Z eff ) is found at 0.284 MeV and varied between 31.75 and 34.30 for the tested glasses; it equaled to 30.29 for the pure TeO 2 glass. The half-value layer (HVL) of the glasses showed a gradual decline with increasing density. The pure TeO 2 was revealed to have thicker HVL than the selected oxyfluoride tellurite glasses. A 1.901-cm thickness of the sample, ZnFWTe1, is required to decrease the intensity of a photon with an energy of 0.284 MeV to one-tenth of its original, whereas 1.936, 1.956, 2.212, and 2.079 cm are required for glasses ZnFWTe2, ZnFWTe3, ZnFWTe4, and ZnFWTe5, respectively.

A series of six samples were prepared based on the chemical composition of 65B 2 O 3  + 20ZnO + (15-x)LiF + xSnO 2 ( where x = 0, 0.25, 0.5, 0.75, 1, and 1.25 mol%) to study the role of SnO 2 on enhancing the optical and radiation attenuation capacity of the prepared glasses. The preparation of the glass series was performed using the melt quenching method at 1100 °C for 60 min. The density of the fabricated samples was measured using an MH-300A densimeter. The optical parameters of the fabricated glasses were calculated based on the spectrum recorded by a Cary 5000 UV-Vis-NIR double beam spectrophotometer in a wavelength range of 200 to 3000 nm. Furthermore, Monte Carlo simulation code and the XCOM online database were used to estimate the gamma-ray shielding capacity of the fabricated samples from 0.244 to 2.506 MeV. The results show enhanced gamma-ray shielding capacity due to the replacement of LiF by SnO 2 . The linear attenuation coefficient at 0.244 MeV was enhanced from 0.352 to 0.389 cm -1 . The half-value thickness of the investigated glasses decreased from 1.967 to 1.784 cm when the increasing addition of SnO 2 from 0 to 1.25 mol%., (© 2022. The Author(s).)