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Radiation-shielding glasses are essential for protecting individuals from the harmful effects of ionising radiation in various industries and medical contexts. Their use is vital for ensuring workplace safety and significantly reducing the risk of long-term health complications resulting from radiation exposure to the eyes. Motivated by this, the (Sm3+, Cu2+) co-doped sodium-zinc-borate glasses were prepared using the melt-quench method. These glasses were then exposed to different doses of gamma radiation, and detailed experimental studies were conducted. Physical parameters such as density, along with other characteristics, were calculated. Detailed analysis of the structural, optical, luminescence, and decay properties was also performed. Computational techniques for Mo-42 and Co-60 were utilised to evaluate the radiation shielding performance of the samples. It was observed that samples with a higher concentration of samarium exhibited better shielding behaviour. The band gap values decreased due to the effects of radiation. Additionally, the variation in density with the radiation dose provided a clear indication of non-bridging oxygen formation due to radiation-induced defects. Energy transfer from samarium to copper ions in the glass was observed at 290 and 402 nm excitations. Colour-correlated diagrams, decay analysis, and colour purity analysis were carried out to understand the dependence of samarium and copper ions in the matrix. The computational evaluation demonstrated that higher concentrations of samarium resulted in better shielding behaviour, and at energies lower than 0.1 MeV, the shielding ability was evident. [ABSTRACT FROM AUTHOR]

Background: Microsponges are one of the advanced drug delivery systems that facilitates precise and controlled release of active ingredients that are suitable for topical and oral use. These porous microspheres are typically sized between 5 and 300 μm, offer benefits including controlled release, stability, and minimized side effects. Manufacturing techniques like quasi-emulsion solvent diffusion and liquid–liquid suspension polymerization are usually employed to prepare microsponges, although various challenges arise from the use of potentially hazardous organic solvents. Main body: Microsponges possess distinct traits such as extended drug release, formulation flexibility, and high drug loading capacity. Entrapment of drugs requires considerations of solubility, stability, and miscibility, while evaluation methods encompass production yield and particle size analysis. Their applications range from dermatological to biopharmaceutical delivery, with diverse products utilizing this technology. Ongoing innovations about microsponges are evident in patents concerning medical dressings and hyaluronic acid delivery systems. Conclusion: Microsponges present a promising avenue in drug delivery, despite many challenges. Current review addresses on limitations and diverse products highlighting commercial viability. Patent activity signifies continued interest, suggesting significant potential for enhancing patient care. [ABSTRACT FROM AUTHOR]

The study focused on preparing and investigating CeO2 dopant concentration on the optical properties of lithium-calcium borate glasses through systematic studies using XRD, RAMAN, UV-visible spectroscopy, photoluminescence and decay measurements. The optical absorption spectral results show that the absorption edge shifted towards the lower energy side as the concentration of CeO2 increased, resulting in a decreased optical band gap. Various excitations (285, 328, 338, and 348 nm) induced luminescence emission in the prepared glasses are studied systematically. It was observed that among all the samples, 0.05 mol% CeO2 doped glass exhibits a bright blue emission under 328 nm excitation compared to other excitations. In particular, the excitation and emission spectra revealed the presence of at least two different emission centres (5d → 2F7/2 and 2F5/2) originating from the Ce3+ ions in the host glass matrix. Furthermore, the non-exponential decay kinetics of the optimised sample (0.05 mol% CeO2) showed a maximum lifetime of 37.6 ns. Furthermore, the CIE colour chromaticity diagram demonstrated 87% purity of the emission. The study provides a comprehensive understanding of the structural and optical properties of cerium-doped lithium-calcium-borate glasses, which can be helpful in the development of new materials for optical applications. [ABSTRACT FROM AUTHOR]

Herein we report the optical and spectroscopic properties of lithium–calcium–bismuth–borate (LCBB) glasses containing Eu3+ prepared via the melt-quenching method, and the prepared samples were systematically characterised through X-ray diffraction (XRD), Raman, ultraviolet–visible–near-infrared (UV–Vis-NIR) and photoluminescence (PL) spectroscopic techniques. The absence of XRD peaks evidenced the amorphous nature of glass. Different borate functional groups were identified from Raman spectra. Urbach energy and radiative properties were evaluated from the UV–Vis–NIR absorption spectra. The phonon energy of the glass samples was estimated by considering the energy differences between the zero-phonon level (ZPL) and phonon side bands (PSBs) present in excitation spectra. Judd–Ofelt (JO) parameters have been evaluated from the luminescence intensity ratios of 5D0 → 7FJ (J = 2, 4) to 5D0 → 7F1 transitions. These parameters have been used to derive radiative properties such as transition probabilities, branching ratios, radiative lifetimes and peak stimulated emission cross-sections for the 5D0 → 7FJ transitions. The JO results and the lifetime decay studies showed that LCBBEu2 glass exhibits higher stimulated cross-section (16.74 × 10–22 cm2) and quantum efficiency (67.80%), which is highest among the reported by other research groups. Also, the LCBB doped with Eu3+ glasses exhibit strong emission in the red region, making them potential candidates for photonic device applications. [ABSTRACT FROM AUTHOR]

Developing the high-efficiency photocatalyst of low-cost synthesis is a more important implication in the field of research. Thus versatile applicable nanomaterial need of search leads us to synthesize WO3:TiO2 (1:2 to 1:8) photocatalysts through the ultra-sonication-assisted co-precipitation method for sensing heavy metal ion (lead) and the degradation of reactive blue 4 dye under visible light irradiation. The synthesized material has been confirmed by the characterization techniques such as powder X-ray diffraction (PXRD) & Rietveld Refinement for the crystal size ranges from 8 to 13 nm. Scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS) for surface morphology and elemental confirmation. The band gap evaluated from Ultra-violet Visible-Diffuse reflectance spectroscopy (UV-DRS) is 3.1–3.4 eV. Having aggregable size, the photocatalyst WO3:TiO2 (1:6) showed better results when compared to other ratios. Electrochemical sensor action for lead ion detection was conducted by graphite assisted with WO3:TiO2 (1:6) electrode paste in 0.1 M KCl electrolyte. Photocatalytic degradation of reactive blue 4 dye was conducted under visible light and achieved 84% degradation. It shows that the better capacitance value of 24.7 × 10−2 F/g for WO3 proves to be a better capacitor application. [ABSTRACT FROM AUTHOR]

The present work aims to study the significant influence of the incorporation of gold nanoparticles (AuNPs) in the Ho3+—doped Li2O + Bi2O3 + B2O3 + P2O5 glasses prepared via the melt quenching method. The prepared glasses were systematically studied using various techniques such as; x-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), differential scanning calorimetry (DSC), ultraviolet–visible-near infrared (UV–vis-NIR) spectroscopy, photoluminescence, and lifetime decay measurements. Furthermore, theoretical JO calculations were performed to investigate and validate the optical properties with experimental results. The structural studies by XRD and HR-TEM reveal the amorphous characteristics of glasses and the presence of metallic gold nanoparticles. The DSC results reveals the thermal stability of the glasses with addition of AuNPs into the glasses as shown by the rise in Tg values from 453 to 498 °C. Optical absorbance spectra demonstrate the existence of 8 electronic transitions in the UV–Vis-NIR region attributable to Ho3+ ions and an intensified SPR peak is observed owing to the incorporation of AuNPs. PL spectra exhibit three distinct, notable emission peaks in the visible wavelength region, whose intensity is greatly affected by incorporating AuNPs due to the reduced NR decay rate. Furthermore, JO analysis was carried out to support the experimental results, which reveals that, the JO parameters are in the order; Ω2 > Ω4 > Ω6, demonstrating the covalency nature between the Ho3+–O2− bond and the adjacent Ho3+ ions. PL emission spectra were used to estimate the chromaticity coordinates, which is in the region of the cool white light region for AuNPs incorporated Ho3+- doped glasses. Amongst all, LBBPH05Au. i.e. (0.5 mol% Ho3+ + 0.001 mol% Au0) doped Li2O + Bi2O3 + B2O3 + P2O5 glass sample exhibits high quantum efficiency (77.2%), low NR decay rate and white light emission in the cool region. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate the transition metal oxides (CuO, TiO2) induced structural, optical, luminescence and elastic characteristics of (60 − x)B2O3 + 20K2O + 10ZnO + 10ZnF2 + xTMO glasses produced via the melt-quenching process. The prepared glass samples were comprehensively studied through various characterization techniques systematically using XRD, FTIR, and UV–Visible spectroscopic techniques. In addition, the elastic properties were evaluated using the Makishima–Mackenzie theoretical model. It was found from the structural studies by XRD show that the glass samples exhibit amorphous characteristics even after doping with TMOs. There is no significant variation in the physical parameters upon adding TMOs, indicating the structural stability of the prepared glasses and the occurrence of non-bridging oxygens in the glass matrix. while FTIR analysis revealed the predominance of borate groups for all the prepared samples. UV–Visible absorption spectral studies demonstrate the presence of prominent electronic transitions originated by incorporating dopant (CuO) in the case of BCu glass samples. In contrast, other glasses (B and BTi) show no signatures. Further, the estimated indirect energy band gap and Urbach energy values were higher than the base (host) glass. The elastic properties such as estimated elastic moduli describe the elastic behaviour of the prepared glasses. Among all the glasses, BCu glass stands out for its exceptional optical and elastic qualities. [ABSTRACT FROM AUTHOR]

Nanocrystalline Ni 1−x Zn x Fe 2 O 4 (where, x = 0.0, 0.2, 0.4, 0.6, 0.8 & 1) samples were synthesized through solution combustion technique using oxylyl de-hydrazide (ODH) as a fuel and the effect of dopant and its concentration on the structural and magnetic properties was investigated. As-prepared samples were characterized using different characterization techniques such as, XRD, SEM-EDS, TEM and Raman spectroscopy for their phase-purity, crystallinity, surface morphology and elemental composition; also magnetic properties were investigated through EPR, Mossbauer spectroscopy and vibrating sample magnetometer (VSM). Rietveld fitted XRD and Raman studies confirm the formation of cubic spinel structured ferrites and substitution of Zn ion at Ni site without formation of impurity phases. No other structural changes were observed and the structure remains in cubic phase with increase of Zn concentration. SEM and TEM micrographs reveal that the particles are agglomerated and the particles size were found in the nano range. Also good stoichiometric composition was observed in all the compositions of Zn substituted Ni ferrite samples. Magnetic measurements (VSM) reveal that pure Ni ferrites exhibits soft magnetic behaviour. Further the ferromagnetic behaviour suppressed with the substitution of diamagnetic Zn ion and with increase of its concentration in Ni ferrites, which was further evidenced in the Mossbauer spectroscopic results. At room temperature, electronic paramagnetic resonance spectra exhibits a broad resonance signal with Lande's g factor varies from 2.23 to 1.95 with increase in Zn content, which is attributed to spin exchange interactions between Fe 3+ , Ni 2+ and Zn 2+ ions also asymmetric EPR spectra was observed. The investigated results show that, Zn substitution has greater impact on the magnetic properties of Ni ferrites due to the diamagnetic nature of Zn, which inturn alters the cationic distribution and the exchange interactions between Ni-Fe and Fe-Fe. [ABSTRACT FROM AUTHOR]

Zn 1−x Al x O (x = 0, 0.01, 0.02, 0.03) thin films were deposited on glass substrate using sol-gel spin coating method and the effect of Al doping on their structural, micro-structural, optical and photoluminescence properties were investigated. The XRD results confirm the single phase nature and the successful substitution of Al at Zn site in ZnO thin films. Further with Al doping, the crystallite size, lattice parameters and film thickness were found to decrease. Also, both AFM and SEM results confirm the formation of spherical grains with lower roughness of the films. Al doped (>2%) films shows ∼ 90% transparency in the visible wavelength region. Widening of band gap (3.18–3.34 eV) was observed with increase in Al doping concentration, which was attributed to the Burstein–Moss band-filling effect. The defect induced luminescence at room temperature was studied by photoluminescence spectroscopy. PL spectra of AZO films show sharp peaks in the visible wavelength region. A detailed analysis of photoluminescence of undoped and Al doped ZnO films indicates the inhibition of defect density of electronic states due to substitution of Al 3+ . The observed emission peaks were attributed to the defect related deep-level emissions. Results suggest possible use of Al doped ZnO films for transparent conducting oxide (TCO) electrodes and light emitting diodes (LED's) applications. [ABSTRACT FROM AUTHOR]