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In this study, the role of TiO2 on the physica, and optical properties as well as the γ-ray protection features of a set of six glass samples with the chemical formula (65-X)B2O3–15BaO–5Bi2O3–15ZnO–XTiO2, where X = 0–10 mol% in the step of 2% have been investigated. The density (ρ) increased gradually from 3.70 to 3.93 g/cm3 and the molar volume (Vm) reduced from 27.71 to 26.72 cm3/mol as the TiO2 content increased from 0 to 10 mol%. By the inclusion of TiO2 in the glass networks, some absorption bands in the ultraviolet and visible regions are formed. Values of the indirect optical band gaps (Eg) were 2.550, 2.510, 2.470, 2.370, 2.270, and 2.180 eV for Ti-0.0, Ti-2.0, Ti-4.0, Ti-6.0, Ti-8.0, and Ti-10.0 glasses, respectively. The linear refractive index (n0) calculated values varied from 2.515 to 2.631. The linear-attenuation coefficient ( μ) followed the order: Ti-0.0 < Ti-2.0 < Ti-4.0 < Ti-6.0 < Ti-8.0 < Ti-10.0. The sample coded as Ti-10.0 glass sample (highest content of TiO2) has the lowest half (HVL) and tenth (TVL) value layer. Within the investigated energy range of within the range: 51.590–19.480, 50.676–19.722, 50.696–19.833, 50.271–20.012, 49.860–20.193, and 49.460–20.376 for the prepared samples Ti-0.0, Ti-2.0, Ti-4.0, Ti-6.0, Ti-8.0, and Ti-10.0 glasses, respectively. Results confirmed that the suggested titanium bismo-borate glasses can be used in the optical field and as alternative materials for radiation shielding applications. [ABSTRACT FROM AUTHOR]

In the present article, samples of erbium (Er)-doped bismo-borate glasses have been fabricated with general chemical compositions: 70B2O3–10CaO–10Li2O−(10-x)Bi2O3− xEr2O3: 0 (Er-0.0) ≤ x ≤ 1 (Er-1.0) mol% using the conventional melt-quench process. The impact of Er3+ ions on the structure and optical (linear and nonlinear) characteristics of Er-0.0/Er-1.0 glass blocks have been investigated. XRD measurements showed the lack in crystallinity of the prepared samples. In the range of UV-Vis measurements, there are absorption bands attributed to the electronic transitions (4f−4f) of Er3+ ions. The absorption bands seen at wavelengths of approximately 366, 379, 409, 452, 490, 523, 545, 653, 797, and 978 nm are associated with electronic transitions from the ground state, 4I15/2, to several excited states, namely 4G9/2, 2G11/2, 2H9/2, 4F5/2, 4F7/2, 2H11/2, 4S3/2, 4F9/2, 4I9/2, and 4I11/2, respectively. The optical band gap (Eg) values ranged from 2.61 to 3.11 eV for Er0.0 to Er1.0 glass samples, respectively. Values of linear refractive index (n0) ranged from 2.498 to 2.374. Values of the nonlinear refractive index varied from 7.76 to 4.99, while the third order non-linear optical susceptibility (χ(3)) values ranged from 5.14 to 3.14 for Er0.0 to Er1.0 glasses, respectively. Therefore, the suggested glasses can be used in several optical applications such as opto-electronic devices. [ABSTRACT FROM AUTHOR]

The influence of nickel-oxide (NiO) addition on the structural, optical, physical properties, and dielectric spectroscopy of lead-borated glass blocks of the chemical form: (70-x)B2O3-25Na2O-5PbO-xNiO: x = 0 (Ni-0.0)-2.5 (Ni-2.5) molar percentage was tested experimentally using various methods. X-ray diffraction measurements confirmed the amorphous character of prepared Ni-glasses. Density increased gradually from 2.5981 to 2.7568 g cm−3, whereas molar-volume declined from 29.0131 to 28.0202 cm3 mol−1 as Ni2+ ions-contenting samples improved from 0.0 to 2.5 mol% in glasses network. In the absorption UV-region, optical-gap energy changed between 2.94 and 2.48 eV. In absorption within Vis-region, the intensity of the absorbed band enhanced gradually with red-shift in their positions as Ni2+ ions content increased. In the absorption NIR-region, an increase in the IR absorption bands was observed and confirmed the enhanced heat-absorption capacity of the investigated glasses as their NiO content increased. Dielectric spectroscopy at frequencies ranging from 50 Hz to 5 MHz of (70-x)B2O3-25Na2O-5PbO-xNiO: x = 0, 0.5, 1.0, 1.5, 2.0, and 2.5 mol% glasses are carried out to determine the impact of nickel doping on dielectric spectroscopy items. Nickel doping gradually increased the dielectric constant. At high frequencies, the transport rate among nearby conductive sites is increased while the shifting length of the charges is greatly reduced which leads to higher conductivity. [ABSTRACT FROM AUTHOR]

Six specimens of iron (II)-doped borate glasses with the following chemical formula: 75B2O3–15PbO–10BaO3–xFe2O3: x = 0.0–0.5 mol% with an incremental step of 0.1 were produced using the traditional melt quench method. The effects of iron ion doping on mechanical, dielectric properties, and radiation protection effectiveness (RPE) of the prepared samples were investigated. The oxygen-packing density (OPD) and molar volume (OMV) increased as iron (II) content increased in the glasses network. Therefore, the created non-bridging oxygen (NBO) increased. Elastic parameters of the investigated samples enhanced as a function of Fe2O3 content. As the molar percentage of Fe2O3 increased from 0 to 5.0 mol%, Poisson's glasses ratio fluctuates between 0.365 and 0.3700. As the energy of the incoming photon increases, the RPE tends to fall below 100% in low-energy regions. The sample with the code Fe2O3-0.5 exhibits the smallest value (R = 0.156498 cm−1) and the largest molar fraction (Fe2O3 = 0.5 mol%), as well as the maximum molar volume and Vickers hardness. Dielectric spectroscopy of manufactured glasses is investigated at various frequencies ranging from 50 Hz to 5 MHz at room temperature to explore chemical alterations caused by iron doping on dielectric spectroscopy components like the dielectric constant ( ε ′ ) and tangent loss (tan δ). Results showed that the dielectric constant drastically declines with a rise in the frequency domains up to 700 Hz for all glasses doped with varying amounts of iron and appears almost constant at higher frequencies for all glasses. The inclusion of iron increased the amount of (NBO) elements in the inside molecular framework of glass, which significantly increased the dielectric constant. [ABSTRACT FROM AUTHOR]

Copper-doped borate zinc sodium fluoride glasses with the chemical formula 70B2O3-10ZnO-(20 − x)NaF-xCuO: x = 0.0 (BZNC0.0)−1.0 (BZNC1.0) mol.% were fabricated via the rapid cooling technique. Physical and linear optical characteristics and photon, electron, proton, and alpha particle attenuation capacities were explored. The glass densities (i.e., ρ) were improved from 2.932 g/cm3 to 2.975 g/cm3 and the molar volume (Vm) decreased from 22.261 cm3/mol to 22.062 cm3/mol for BZNC0.0 to BZNC1.0 glasses. The direct ( E OBG Direct ) and indirect ( E OBG Indirect ) optical band gap decreased with increasing Cu2+ ions in the glassy networks. The direct optical band gap ( E OBG Direct ) decreased from 3.85 eV to 3.28 eV, whereas the indirect optical band gap ( E OBG Indirect ) varied between 3.29 eV and 3.02 eV. The Urbach energy (EU) was enhanced from 0.084 eV to 0.131 eV. The extinction coefficient (k), refractive index (n), surface energy loss function (SELF), and volume energy loss function (VELF) were improved as the molar ratio of Cu2+ increased in the glass structural backbone. The mass attenuation coefficient (MAC) and linear attenuation coefficient (LAC) were enhanced as Cu2+ ions increased. The results of the induced effective atomic number (Zeff) of various interactions confirmed that (Zeff)photon > (Zeff)beta > (Zeff)proton > (Zeff)alpha. Thus, the proposed glasses may be utilized in several opto-radiation shield applications. [ABSTRACT FROM AUTHOR]

The effect of copper ions on the structural, mechanical, shielding and dielectric features of borate zinc-fluoride glasses was investigated. The elastic moduli of the proposed glasses increased linearly as a function of CuO mol.% content in the glassy network. Young's modulus increased from 34.390 GPa to 35.093 GPa at low and high CuO mol.%. In terms of the electron stopping power (ESP), the addition of CuO into the glass matrix had no significant influence on the ESP. In all scattering regions, it was found that the Vickers hardness (Hv) and radiation protection effectiveness values increased linearly as a function of the CuO mol.% concentration. The real component of the permittivity (ε′) of all investigated glasses loaded with varying concentrations of CuO mol.% decreased dramatically with increasing frequency during the low-frequency interval. The ε′ value decreased slightly with increasing CuO content up to 0.4 mol.% and then increased with a further increase in concentration. The recorded loss tangent (tan δ) for all the examined glasses had two relaxation peaks at 800 Hz and 100 kHz; however, copper doping increased their intensity and shifted them to a lower frequency. [ABSTRACT FROM AUTHOR]

In this work, the role of insertion cobalt(II) on the physical properties, dielectric spectroscopy, and photon attenuation parameters of the prepared glasses 25NaF-10ZnO-(65-x)B2O3-xCoO-0.6Y2O3: x = 0.0 (Co-0.0) ≤ x ≤ 0.5 (Co-0.5) mol% has been investigated. The amorphous state of samples verified via the XRD measurements. The density (ρ) ∈ [2.9824, 3.0058 g.cm−3]. The molar volume (Vm) ∈ [21.868, 21.715 cm3.mol−1] as an increase of CoO from 0.0 to 0.5 mol% in the glass network. Dielectric spectroscopy of borate glass loaded with varying cobalt content was investigated throughout frequency range from 50 to 5 MHz. The recorded dielectric constant at 3 kHz was enhanced from 14.4 to 17.8 by cobalt doping. The dependency of tangent loss (tan δ) for all investigated glasses on frequency is normal behavior with dielectric relaxation which is enhanced and shifted by cobalt doping. At the photon energy (E = 0.015 MeV), the mass-attenuation-coefficient (MAC) values were 10.192, 10.246, 10.300, 10.354, and 10.408 cm2/g for the samples Co-0.0, Co-0.1, Co-0.2, Co-0.30, Co-0.4, and Co-0.5, respectively. These MAC values are corresponding to as increment of 0.216 cm2/g between the low and high CoO contents presented in the glass samples. Values of half value layer (HVL) of all proposed specimens were more significant than that of RS-360 and RS-520 commercial glasses. Results confirmed that the suggested glasses are suitable for radiation attenuation. [ABSTRACT FROM AUTHOR]