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The composition and temperature-dependent dc conductivity of (Ge20Se18Te62)100-xIx (x = 0 and 8) glasses have been studied. The activation energy at constant current decreases, whereas with composition, it increases. The I–V characteristic curves for the glassy compositions show threshold switching. Iodine content shows a remarkable effect when introduced in Ge-Se-Te glasses on the switching properties. Variation in the threshold voltage (Vth) with composition decreased from 334 to 308 V. The thickness and temperature dependency on Vth is also examined. With increasing temperature, the Vth decreases exponentially, whereas it increases as T2 with an increase in the thickness of the glass samples. The thermal breakdown ΔTbreakdown is also calculated. The threshold switching properties may be explored for numerous applications such as high-speed electronic memory and selector devices.

In the present work, the nanoparticles of spinel bismuth Chromites (BiCr2O4) are prepared using sol gel method. We have developed a novel technique to achieve longer stability and higher ionic storage of MXene/BiCr2O4nanocomposite by using co-precipitation method. Structural and morphological properties of the prepared nano-structures are thoroughly investigated. The band gap is seen to reduce from 2.08 eV for MXene to 1.90eV for MXene/BiCr2O4 nanocomposite which encompasses all the earlier stated values. The average particle size of nanocomposite MXene/BiCr2O4 is 11.15 nm. The EDX analysis is performed to confirm the elemental composition of the prepared nano-composites. Composite electrodes are then electro-polymerized on the coating of glassy carbon electrode. The value of specific capacitance is measured to be 455.0 F/g, suggesting the plausible usage of the synthesized material in super capacitance applications. The prepared MXene/BiCr2O4 nanocomposites can be used as efficient promoters and electrode materials, based on the attractive properties like reduced band gap, high electrochemical stability, and excellent value of specific capacitance.

Optoelectronic and thermoelectric properties of A3AsN (A ¼ Mg, Ca, Sr and Ba) compounds in cubic and orthorhombic crystallographic phases are investigated using FP-LAPW method along with GGA and GGA-mBJ potentials based on DFT. Electronic properties shows that all the compounds both in cubic and orthorhombic crystallographic phases are direct band gap semiconductor at central symmetry. The calculated band gap for the cubic and orthorhombic phases ranging from2.43 to 0.084eV through GGA and GGA-mBJ. The calculated band gap not only decreases with cation replacement but also diereses going from cubic to orthorhombic phase. The result revel that all the compounds are optically active in visible and infrared region of electromagnetic spectrum. Due to the narrow band gap semiconducting nature of these compounds their thermoelectric parameters are also calculated which shows that these compounds are efficient to use as the active thermoelectric materials.

This work investigates the effects of TeO2 and B2O3 on photon, neutron, and charged particle transmission properties of Bi2O3-BaO-LiF glass system. Photon transmission parameters were obtained via narrow beam setup simulation via FLUKA and those obtained from experimentally proved XCOM calculations. The attenuation factors of $$ {\left(\raisebox{1ex}{$\mu $}\!\left/ \!\raisebox{-1ex}{$\rho $}\right.\right)}_{IS} $$ and $$ {\left(\raisebox{1ex}{$\mu $}\!\left/ \!\raisebox{-1ex}{$\rho $}\right.\right)}_{PP} $$ control the value of $$ \raisebox{1ex}{$\mu $}\!\left/ \!\raisebox{-1ex}{$\rho $}\right. $$ at energies greater than 1.5 MeV; however, the region of influence differs for both absorption processes. While $$ {\left(\raisebox{1ex}{$\mu $}\!\left/ \!\raisebox{-1ex}{$\rho $}\right.\right)}_{IS} $$ peaks occur at 3 MeV, the influence of $$ {\left(\raisebox{1ex}{$\mu $}\!\left/ \!\raisebox{-1ex}{$\rho $}\right.\right)}_{PP} $$ becomes appreciable at E > 5 MeV. The values of linear attenuation factor (μ) ranged from 0.2119–0.5283, 0.2085–0.5248, 0.1837–0.4676, 0.1639–0.4223, 0.1519–0.3971, 0.1370–0.3638, and 0.1222–0.3315 cm-1 as B2O3 increased from 0 to 60 mol % with step of 10, respectively. The spectra of projected range (R) of the ions and CSDA range of electrons show that the TSP of electrons in the glasses increases as B2O3 increased from 0 to 60 mol % for energy lower than 5 MeV; however, it reverses at 10 MeV. The ability of the present glass system for stopping the transmission of various radiation beams reveals its potential use for shielding applications in medical and nuclear facilities.

In this paper we report the structural, thermal, microstructural and infrared transmission properties of iodine doped (Ge20Se18Te62)100 – xIx (where x = 0, 8) chalco-halide glasses. The density of the specimen has been calculated experimentally. Differential thermal calorimetry shows a single glass transition temperature but two crystalline peaks. The role of annealing (503 and 593 K for 2 h) has also been taken into account to investigate the structural, microstructural, and infrared transmission properties. X-ray diffraction study has revealed that on annealing there is an origin of hexagonal Te and orthorhombic GeSe2 microcrystals which are further supported by scanning electron microscopy.

Silver–palladium (Ag/Pd) bimetallic nanoparticles were synthesized by greener way using Catharanthus leaf extract. The synthesized silver/palladium bimetallic nanoparticles were used to degrade the safranin O textile dye through photo catalytic activity and the free radical scavenging property was evaluated by DPPH assay test. Silver/Palladium bimetallic nanoparticles were synthesized by biogenic reduction method using silver nitrate and palladium chloride precursors assisted with CRL extract. The synthesized Ag/Pd bimetallic nanoparticles’ morphological and particle size were evaluated by the SEM/TEM image. The particle size was found to be within the nanoscale range of 15–30 nm. The 98% maximum dye degradation for 40 min time duration was achieved by the photocatalytic activity of silver/palladium bimetallic nanoparticles through UV light irradiation on safranin O textile dye and simultaneously antioxidant activity of silver/palladium bimetallic nanoparticles was also tested through DPPH assay test. The free radical scavenging efficiency was calculated for extract and extract with silver/palladium nanoparticles and was found to be 48.2% and 70.2%, respectively and revealed that the silver/palladium nanoparticles have 2.34 times higher scavenging activity when compared with Catharanthus leaf extract.

Recently, many studies trended to develop new glass systems to serve for various radiation applications. In this article, we report on the radiation attenuation and shielding performance of the Er/Cd/Li/Gd/Si glass system in the chemical form of 50SiO2·30Li2O·(19 − x)CdO·1Gd2O3·xEr2O3 (here, 0 ≤ x ≥ 2.5 mol%). The shielding performance (LAC, MAC, MFP, EAC, HVL, EBF, EABF, and FNRC) is investigated by using the Monte Carlo method (via Geant4 simulations) and theoretical calculations (via Phy-X approach). The obtained results indicate that the Er2O3 addition has a significant influence on the attenuation performance of the present glasses. We also found that the maximum (minimum) value of MAC is obtained at photon energy of 15 keV (10 meV) with the corresponding value of 20.537 (0.028), 22.525 (0.0283), 24.44 (0.0287), 26.286 (0.0290), and 28.067 (0.0293) cm2/g for SLGC-E1, SLGC-E2, SLGC-E3, SLGC-E4, and SLGC-E5 respectively. This rivals the performance of commercial glass shields (RS-253), concretes (ordinary and barite), and recently developed and studied glass (TBZP10 glass). It can be concluded that the SLGC-E5 glassy material has promising attenuation properties to use for the radiation shielding applications.

Nebulizer spray pyrolysis (NSP) technique has been successfully employed for the deposition of well-dispersed highly homogeneous spindle-shaped yttrium-doped cerium oxide (YDC) films. Optical studies revealed a decreasing trend of transmittance with the increasing Y doping percentage up to 20% and then increase in transmittance at 25% either due to the increased crystal defect induced photon scattering or the increased metal-to-oxygen ratio at higher Y doping. PL spectra showed four distinct broad peaks at 3.34 eV (near-band-edge emission (NBE) at UV), and 3.14, 2.91 and 2.65 eV (deep-level emission (DLE) in the visible spectra at violet, blue and green, respectively) corresponding to the wavelengths 365, 394, 425 and 465 nm, respectively. XRD studies confirmed the polycrystalline cubic fluorite single-phase structures preferentially orientated along (200) and (111) reflections without any impurity peaks. SEM images showed that YDC films are grown with small granules containing spherical-shaped particles having many cracks and patches. The average width of tiny granules inside the well-aligned taper-like structures is found within the order of 138 nm. The observed changes in the rectification ratio of p-Si/n-YDC diode with voltage are allied to the corresponding changes in both series (Rs) and shunt resistances (Rsh) of the heterojunction. The transient photocurrent characteristics indicate that the prepared heterostructure is highly stable and has quick response, which advocates the use of prepared heterojunction device in UV detector and white light photodetector applications.

This research article aims to study the effect of CdO addition on the radiation shielding characteristics of boro-tellurite glasses in the composition of 50B2O3 - (50-x) TeO2- xCdO, where x = 0, 10, 20, 30, 40 and 50 mol%. These glasses were exposed to gamma radiation and the transmitted gamma photons were evaluated for energies varying from 15 keV to 15 MeV using Geant4 simulation toolkit. The number of transmitted photons was then used to characterize the gamma shielding for the studied glasses in terms of linear/mass attenuation coefficients, MFP, Zeff, and HVL. The simulation outcomes were theoretically confirmed by using Phy-X software. The beta (electron) shielding characterization of the involved glasses was also investigated by determining the projectile range and stopping power using ESTAR software. Additionally, the fast neutron shielding characterization of the glasses was achieved by evaluating removal cross-section (ΣR). The results reveal that the CdO has a small influence on the shielding performance of the boro-tellurite glasses against gamma, beta, and neutron radiations. The shielding performance of the boro-tellurite glasses was compared with that of common shielding materials in terms of MFP. It can be concluded that the boro-tellurite glasses regardless of the concentration of CdO content have promising shielding performance to be used for radiation applications.

Reduce graphene oxide (rGO) aerogels with different precursor graphene oxide sheet sizes are synthesized using L-ascorbic acid reduction followed by an ambient pressure drying method. The sheet sizes determine the oxygen functionality content during aerogel formation, which subsequently affect its structural properties. The optimized sheet size renders strong parallel sheet stacking to provide mechanical strength that withstands capillary action during aerogel formation with a high surface area (190.40 m2 g−1) and pore volume (0.261 cm3 g−1). Such surface properties enhance the electrochemical properties of rGO aerogel (182 F g−1 at 0.75 A g−1) and render it to be an excellent electrode material for a supercapacitor.

CuO thin films deposited using SILAR coating technique with various dip-cycles. The prepared thin films were characterized to elucidate the structural and morphological features using analytical techniques such as XRD and SEM, respectively. It was found that along with the thickness of CuO films, the crystallinity and morphology of the deposited films have changed appreciably. The optical, electrical, and photosensing properties were also studied for deposited films. The optical and electrical properties for the thin film prepared with 100 dip-cycles were found best as compared to 50, 75, 125 dip-cycles, this may be due to improved crystallinity and uniform distribution of nanoclusters over the substrate. From the UV absorption studies, it was found that the CuO-100 thin-film has the highest absorption and a low bandgap of 1.67 eV. Also, the CuO with 100 dip sample exhibits a minimum resistivity of 2.98 × 102 Ω cm that leads to a higher carrier concentration of 4.63 × 1013 cm−3 and mobility of 4.53 cm2V−1 s−1. The I–V characteristics of all the deposited CuO samples were investigated and the CuO-100 dip cycle thin film is found to have a lower ideality factor of 5.4. Additionally, the Cu-100 thin film reveals a high responsivity and external quantum efficiency values of 1.67 × 10−1 A/W and 54%, respectively. Thus, in the SILAR dip-coating technique, the dipping cycles influence the CuO formation as well as their properties.

The gamma-ray and fast/thermal neutron shielding properties of bismo-borate glasses modified with Nd2O3 in the form B2O3–Bi2O3–SrO-Nd2O3 (BBSN0.0-BBSN5.7) were investigated. The newly developed Phy-X/PSD software and Geant4 simulation code were performed to achieve this goal by evaluating several parameters such as MAC, gamma photons dose rate, FNRCS, and scattering/absorption lengths and cross sections for thermal neutrons. At low photon energy; 0.015 MeV, MAC values varied from 76.72, 76.57, 76.43, 76.29, 76.10, and 75.93 cm2 g−1 for BBSN0.0, BBSN1.0, BBSN2.0, BBSN3.0, BBSN4.3, and BBSN5.7, respectively. The HVL followed reversible trend as follows; BBSN0.0 > BBSN1.0 > BBSN2.0 > BBSN3.0 > BBSN4.3 > BBSN5.7. The highest values for Zeff were found at low energy photon range (0.015 MeV) with the values of 76.71, 76.35, 76.00, 75.65, 75.21, and 74.75, while the lowest values were found at 1.5 MeV; 21.32, 21.42, 21.52, 21.61, 21.73, and 21.87 for BBSN0.0 – BBSN5.7, respectively. The gamma dose rate has a dramatic decrease with increasing the glass thickness from 1 mm to 5 mm. Furthermore, glasses with the highest concentration of Nd2O3 show the best thermal/fast neutron shielding capability among the investigated glasses. One can conclude that BBSN5.7 glass owns the best shielding capacity among all BBSN glasses due to the highest LAC values comparing to other selected ones.

The authors reported the data found by FT-IR spectroscopy, ultrasonic velocities, DTA and, optical investigations of (50-x) Na2B4O7–30PbO2–20SiO2–xTiO2 where x = (0, 10, 20, 30, 40, and 45) mol%. The structure changes of these glasses will be studying by FT-IR spectra. The mechanical properties have been associated with the results of FT-IR spectra. It was noted that the ultrasonic velocities, elastic-moduli, and density physical properties of these samples increased. The obtained results will discuss in terms of structural changes due to the addition of TiO2. Optical feature spectra are recorded at room temperature. The Urbach’s energy (Eu) of the prepared samples has been estimated. Polarizability and basicity of the prepared glasses according to the refractive index and optical bandgap have been investigated. The nature of the produced glasses and glass–ceramics was examined by (XRD) analysis.

Herein, we report the effect of synthesis temperature on the morphologies, optical and electronic properties of magnesium oxide (MgO) nanostructures. The MgO nanostructures were synthesized at different temperatures, i.e., 100 °C, 300 °C, and 600 °C by simple chemical reaction process and their morphology, particle size, optical, and electrical properties were examined by different techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and UV-Vis. spectroscopy. The morphological investigations revealed that various morphologies of MgO nanostructures, i.e., nanoparticles, nanosheet networks, and nanoneedles were synthesized at 100 °C, 300 °C, and 600 °C. The XRD results confirmed that with increasing the synthesis temperature, the crystallinity of the synthesized nanostructures increases. Further, the dielectric properties and AC conductivity at various frequencies for MgO nanostructures were studied which revealed that the dielectric losses decrease with increase in frequency and temperature. In addition, the observed band gap decreases from 4.89 eV to 4.438 eV (100 °C to 600 °C) representing its increase in the conductivity.

Herein, we report the facile microwave-assisted synthesis, characterization and photocatalytic degradation applications of Bismuth ferrite heterostructures composed of interconnected nanosheets (BHNs). The synthesized materials were subjected to several analytical studies such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and UV-visible spectroscopy in order to examine the morphological, structural, optical and photo catalytic properties. The structural and morphological characterizations confirmed the rhombohedral perovskite crystal structure and the formation of heterostructures composed of interconnected nanosheets for the synthesized material. The compositional characterization revealed that the synthesized material is bismuth ferrite with high purity. The BHNs were further used as efficient photocatalyst for the photocatalytic degradation of highly hazardous pollutant methyl orange under sunlight irradiation. The sunlight driven photocatalytic experiments revealed ~86% photodegradation of methyl orange dye in 150 min. The presented work revealed that the synthesized BHNs are excellent material for the photocatalytic degradation of various organic contaminants and hazardous pollutants.

New heterometallic complex [NiCu(NO3)2(H2O)2] (1) was prepared via the reaction of aqueous solutions of (oxalic acid, nickel nitrate and copper nitrate). Mixed oxide CuO-NiO was successfully obtained with different morphological structures (2) and (3) through the annealing of 1 at different temperature 300 °C and 600 °C, respectively. The materials were characterized using FT-IR, TGA, XRD and SEM. As showed from XRD data, with increasing the calcination temperature the crystallinity of CuO-NiO in sample 3 was improved and the diffraction peaks exhibited narrower and stronger than CuO-NiO in sample 2. The average size of CuO-NiO crystals obtained was calculated from Debye-Scherrer equation and found to be 16.65 nm. To assemble the working electrode of 2-aminophenol (2-AP) chemical sensor, a thin layer of CuO-NiO NPs was deposited on glassy carbon electrode (GCE) with conducting binder and used to detect 2-AP in aqueous medium successfully. The chemical sensor is exhibited the higher stability, good sensitivity (20.2729 μAmM−1 cm−2) and enhanced electrochemical activity at room conditions. Therefore, the fabricated chemical sensor with active CuO-NiO NPs may be an effective and sensitive sensor for detection of hazardous materials by reliable I–V method for broad scales environmental safety of and healthcare sectors. Keywords: CuO-NiO, Mixed oxides, 2-aminophenol sensor, Electrochemical method, Glassy carbon electrode, Environmental safety.

Herein, we report the facile synthesis of Iron oxide@Pt core-shell nanoparticles (NPs) by facile two step synthesis process. The first step follows the growth of iron oxide nanoparticle by thermal decomposition process while the second step deals with the formation of iron oxide@Pt core-shell nanoparticles by the chemical reduction method. The synthesized core-shell nanoparticles were characterized by several techniques and used for the catalytic reductive translation of Cr(VI) to Cr(III) in the presence of formic acid by a UV-vis spectrophotometer. The UV photo-spectrometer analysis confirmed the conversion efficiency from 12% to as high as 98.8% at the end of 30 minutes. Thus, the presence of Iron oxide @Pt core-shell nanoparticles (NPs) can be effectively used as a catalyst for the reducion of Cr(VI) to Cr(III) ions. Additionally, antibacterial studies were performed for the prepared core-shell nanoparticles against two bacterial strains, i.e., gram (+ve) Staphylococcus Aureus (S. Aureus) and gram (-ve) Escherichia Coli (E. Coli).

Herein, we report a simple synthesis, characterization and photocatalytic degradation application of composite NiO-WO₃ nanoparticles. The nanoparticles were synthesized by facile low-temperature method and characterized by several techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Vis diffuse reflectance spectra (DRS). The synthesized NiO-WO₃ nanoparticles were used as efficient photocatalyst for the photocatalytic degradation of Eosin yellow (EY) dye. Interestingly, the synthesized photocatalytic exhibited a significant visible-light driven photocatalytic degradation of Eosin yellow (EY) dye. Under optimized conditions (pH = 5, catalyst dosage = 3 μM and initial dye concentration= 1.0 g/L), the obtained photo degradation of EY dye was above 95% in 180 min under visible light irradiation. Remarkably, reusability of the prepared photocatalyst was also observed and the photo-degradation reactions follow the pseudo-first-order model.

Spinel ferrites are attractive for high frequency applications due to their larger direct current (dc) resistivity and low dielectric loss. In the present work, Co0.6Zn0.4HoxFe2-xO4 (x = 0.00 and 0.1) spinel ferrites were prepared by sol-gel method. The X-ray diffraction pattern showed that both samples had cubic spinel structure, while in sample (x = 0.1), the secondary phase (HoFeO3) was also observed. The dc resistivity was increased with the addition of holmium ions. As the temperature increased, the dc resistivity was decreased by proving their semiconducting nature. The dielectric properties were also measured as a function of temperature and frequency. The sample which was composed by the substitution of holmium ions contained low value of dielectric loss. The magnetic properties were also experimentally measured by applying the field up to 2000 oersted. The small area covered by hysteresis loop proved that both samples possessed soft nature of magnetic materials.

Spinel ferrites with composition MnLayFe2-yO4 (y = 0.00, 0.025, 0.05, 0.075, 0.10) were manufactured via the sol–gel route and characterized under different techniques to evaluate the microwave, magnetic, structural and electrical behavior. All the samples have cubic structures as perceived from XRD data. The impedance became enlarged with an increase of rare earth ions. Hysteresis loops (M vs. H) were drawn on behalf of VSM data within the fixed range of − 2 to + 2 KOe. Remanence magnetization and saturation values were decreased with the substitution of rare earth contents. Microwave properties were measured using cavity perturbation. The real and imaginary parts of permittivity and permeability values gradually decreased with increasing frequency. The perceived consequences recommended the present system can be employed in microwave absorption applications.

Te-based chalcogenide glasses own the most comprehensive infrared window among amorphous materials and have far-infrared applications such as CO2 detection. Nevertheless, the glass forming ability and thermal stability decrease for higher Te content chalcogenide glasses. Here, we report the effect of Ga addition on Te-based chalcogenide glasses by presuming that the addition of Ga may develop the configurational disorder and hence may improve the glass forming ability and thermal stability. Ge10Te80Se10-xGax (x = 0, 2, 4, 6, 8, 10 at %) bulk chalcogenide glassy alloys have been synthesized via melt quench technique. The role of Ga is studied through a semi-empirical approach. The result shows that the system is in rigid mode (total number of mechanical constraints >3). The density of the system shows an increase which is further supported by a decrease in free volume percentage. Mean bond energy and glass transition temperature have also been investigated. The energy gap shows a decrease with increase in Ga at. % and the behavior are correlated with the decrease in average single bond energy (72.7 kJ/mol to 69.7 kJ/mol) and electronegativity (2.14–2.06) of the system. From the results of covalent character (>90%), it is estimated that the compositions may be used to form stable glasses, which may be helpful in the development of an infrared system.