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In the present study, Sr0.7Bi0.2TiO3 is mixed with [(K0.5Bi0.5)(Mg1/3Nb2/3)O3] to form a solid solution of [(1 − x)SBT–x(KB)(MNb), x = 0.02, 0.04, 0.06, 0.1]. From the XRD results, it is indicated that KB is the main substituent for SBT ceramic at the A‐site. The breakdown strength (BDS) of ceramic gradually increases with an increase in doping content and achieves a high value of 280 kV/cm for x = 0.06. In addition, the 0.94SBT–0.06(KB)(MNb) ceramic shows excellent temperature stability (−55 to 140°C), a high recoverable energy density (Wd)—2.6 J/cm3, and an efficiency (η)—88% at 280 kV/cm. Therefore, 0.94SBT–0.06(KB)(MNb) ceramic is one of the possible materials for energy storage capacitor applications. [ABSTRACT FROM AUTHOR]

(1 − x)Sr0.7Bi0.2TiO3-xBi(Mg0.5Ce0.5)O3 (x = 0.02, 0.04, 0.06, and 0.1) ceramics were prepared through the solid-state reaction method. Structural, microstructural, dielectric, and energy storage characteristics were thoroughly examined. A dense microstructure with a single perovskite phase was obtained for x ≤ 0.06. A high energy storage density of ~ 1.86 J/cm3, recoverable energy density of ~ 1.67 J/cm3, and a high efficiency of ~ 90% at a breakdown electric field strength of 240 kV/cm were achieved for x = 0.06. Further, this composition also shows a ΔC/C25°C in the range of − 55 to 135 °C. The above characteristics indicate that this material is a suitable candidate for power-pulsed capacitor applications. [ABSTRACT FROM AUTHOR]

Glass samples were synthesized according to 10Li2O + 20CuO + xBi2O3 + (70 − x)B2O3, where x = 0, 10, 20, 30, 40 mol% by the melt-quenching method. The ability of the prepared glass to protect against gamma rays and neutrons was examined experimentally and theoretically. The mass attenuation coefficient (MAC) was calculated experimentally at energies of 0.662, 1.173, and 1.333 MeV using 137Cs and 60Co sources. The obtained results were compared with the theoretical ones using a Phy-x/PSD software program version 0.1.0.0. It was found that the experimental and theoretical results are very agreed upon. Moreover, other nuclear radiation shielding parameters were evaluated. The results showed that the addition of bismuth oxide leads to an improvement in the ability of the composite glass to attenuate gamma rays by increasing the values of MAC and Zeff, while it led to a decrease in the HVL and MFP, as well as the EBF and EABF. The results also showed that the addition of copper oxide led to an improvement in the ability of the present glass to slow down fast neutrons. Sample BiS40 showed the best result for gamma ray attenuation and sample BiS10 gave the best result for fast neutron removal cross section. The results were compared with some materials used for gamma ray shielding and fast neutron removal cross section, and it was concluded that samples Bi40 and BiS10 outperformed all commercial materials. [ABSTRACT FROM AUTHOR]

Nuclear radiation shielding parameters for glass samples composed of 20 mol.% Li2O-40 mol.% ZnO-40 mol.% P2O5: x wt.% Yb2O3 (x = 0, 0.2, 0.4, 0.6, 0.8, 1, 2) were evaluated. The samples were synthesized using the melt-quenching technique. The prepared samples were encoded Yb0.0, Yb0.2, Yb0.4, Yb0.6, Yb0.8, Yb1 and Yb2 according to the Yb2O3 content. X-ray diffraction (XRD) reveals that all the prepared samples were amorphous. The gamma ray shielding parameters such as mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half value layer (HVL) and mean free path (MFP) were obtained using Phy-X/PSD and XCOM software programs. The atomic cross section (ACS), electronic cross section (ECS), effective atomic number (Zeff), and electron density (Neff) were evaluated, as well as exposure buildup factor (EBF) and energy absorption buildup factor (EABF). The MAC values were found to be 26.304–31.872 cm2/g for Yb0.0–Yb2, respectively. The HVL and MFP values were found to be (0.008–0.007 cm) and (0.012–0.010 cm) for Yb0.0–Yb2, respectively. The ACS and ECS values were found to be (9.912 × 10−21 cm2/g) up to 13.06 × 10−21 cm2/g) and (3.990 × 10−23 up to 4.900 × 10−23 cm2/g) for Yb0.0–Yb2, respectively. The Zeff and Neff values were found to be (24.83–26.64) and (6.59 × 1023 up to 6.50 × 1023 electrons/g) for Yb0.0–Yb2, respectively. The results showed that the addition of Yb2O3 improves gamma-ray shielding properties of the glass. On the other hand, adding Yb2O3 to the prepared glass leads to a decrease in the removal cross section for fast neutrons (ƩR) from 0.103 to 0.096 cm for Yb0.0–Yb2, respectively. The gamma-ray shielding parameters for the present samples were compared with commercial concrete and glass used as gamma ray shields. [ABSTRACT FROM AUTHOR]

This study examines the structure and properties of stainless steel coatings deposited to incorporate large concentrations of nitrogen along with varying amounts of titanium. Deposition was carried out using magnetron co-sputtering of stainless steel and titanium from separate targets in a mixed Ar/N2 gas atmosphere. Composition analysis by X-ray photoelectron spectroscopy showed that while films with up to 4 at.% Ti exhibited little change in nitrogen content (compared to films deposited without Ti) and remained sub-stoichiometric with respect to N content. Films with 7–8 at.% Ti had a higher N level and further increasing the Ti level to 11–12 at.% resulted in stoichiometric N levels. X-ray diffraction showed that the films all had a nominally FCC structure with no additional phases. However, the peak locations for the (111) and (200) reflections indicated a distorted lattice characteristic of the S-phase, with calculated c/a values ranging from 1.007 to 1.033. The Ti additions, along with the corresponding increase in N content, helped reduce the extent of lattice distortion. The film microstructure of the higher (11–12 at.%) Ti films also showed higher density, lower surface roughness, and a finer grain structure. As a result, these films had a higher hardness compared to the sub-stoichiometric films, with hardness levels in the range of 18–23 GPa, typical of transition metal nitrides coatings. [ABSTRACT FROM AUTHOR]

In the pursuit of lead-free perovskite materials suitable for harnessing solar energy, a recent discovery has emerged regarding Cs 2 TiBr 6 . This compound has garnered attention as a prospective candidate, exhibiting favorable optical and electrical characteristics alongside exceptional resilience when subjected to environmental strains. This study details the successful synthesis of non-hazardous metal halide nanoparticles of Cs 2 TiBr 6 via the slow cooling method. Comprehensive investigations into the structural, optical, and dielectric characteristics have been undertaken. The temperature sensitivity of various electrical properties, including the dielectric constant, loss factor, electric modulus, and AC/DC conductivity, is evident in this perovskite material. This phenomenon is observed across a frequency range of 1 to 10 7 Hz. Furthermore, examination of the Nyquist plot highlights the distinctive contributions of both grain and grain boundaries to the overall impedance characteristics. In the high-frequency range, it is observed that the dielectric constant exhibits an upward trend as the temperature rises. Examination of the adapted Cole-Cole plot unveils that both space charge and free charge conductivity escalate with increasing temperature, while concurrently, the relaxation time experiences a reduction with the temperature's ascent. We observed an asymmetrical pattern in the electric modulus spectra at varying temperatures using a modified Kohlrausch-Williams-Watts equation. This asymmetry is consistent with the inherent non-Debye nature of perovskite materials. Additionally, as the temperature increases, we note a shift in the imaginary component of the electric modulus spectra, transitioning from a non-Debye character towards a semi-Debye nature, though it does not achieve a strictly Debye-type response. This transformation indicates the semiconducting properties of the material. We elucidate the AC conductivity behavior in Cs 2 TiBr 6 by employing the non-overlapping small-polaron tunneling (NSPT) mechanism as the basis. The activation energy, as determined from both the modulus spectra and DC conductivity, aligns closely, providing robust evidence for the congruence between the relaxation dynamics and the conduction mechanism. In addition to these attributes, Cs 2 TiBr 6 exhibits a substantial dielectric constant coupled with negligible dielectric loss, thus establishing its potential suitability for energy harvesting devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)