Radiation shielding materials are essential for balancing the benefits and risks of ionizing radiation. In this prospective, we have prepared a series of glasses with composition ...(70-x)B2O3–15BaO–10PbO–5WO3-xBi2O3 (where x = 0, 5, 10, 15, 20 mol %) for varying concentrations of Bi2O3 using melt-quenching method. Their physical, thermal, structural, mechanical, optical, and radiation shielding properties were evaluated. XRD scans confirm the amorphous nature of prepared glasses. As Bi2O3 content increases from 0 to 20 mol%, the density of the glasses rises from 3.155 to 4.578 g/cm3. Thermal studies show enhanced properties when substituting B2O3 with Bi2O3. FTIR studies reveal the presence of BO3, BO4, BiO3, and BiO6 structural units in the glasses. Mechanical properties, evaluated by Makishima–Mackenzie model, decrease as Bi2O3 concentration rises. Optical absorption studies suggest decreasing band gap energy (2.908–2.254 eV for indirect transitions), implying the possibility of the non-bridging oxygen formation. In the context of radiation shielding, mass attenuation coefficients (MAC) of the produced glasses were determined both experimentally and by using the Phy-X/PSD program, and their agreement validates the accuracy of the experimental findings. Additionally, various other shielding parameters such as linear attenuation coefficient (LAC), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), and effective atomic number (Zeff) have been evaluated and interpreted. The results indicate that the substitution of Bi2O3 directly impacts the shielding ability of the glasses. The BBi-20 glass sample, containing 20 mol% of Bi2O3, emerges as the superior candidate for shielding, showing the highest MAC (0.1284 and 0.0986 cm2/g at the energies 0.511 MeV and 0.662 MeV respectively), LAC, and Zeff, along with minimum HVL, TVL, and MFP values. Comparison of MAC values with standard shielding materials confirms the potential of the produced glasses for gamma shielding applications, highlighting their promising structural and optical properties.
A conventional casting method was used to produce promoted polyvinyl alcohol (PVA) films via rubrene additive. The 1.2 g of PVA dissolved in 120 ml of distilled water and doped with various ...concentrations (0, 0.1, 0.3 and 0.4 wt%) of rubrene dye. The influence of rubrene dopants on the structural properties of PVA was studied using FTIR and XRD techniques. The semicrystalline nature of the PVA polymer was established by the XRD pattern. FT-IR analysis shows changes in peaks intensities of PVA and their widths are expanded in the presence of rubrene dopants which indicates the interactions between the functional groups of PVA and the rubrene dopants. XRD patterns exhibit the existence of rubrene inside the PVA structure leads to form cross-linking which enhances the amorphous nature within the doped PVA samples. The optical characteristics were investigated using spectrophotometric measurements of transmittance T(λ), reflectance R(λ), and absorbance A(λ) in the spectral range of 200–2500 nm. The indirect and direct optical band-gap values of PVA films decreased from 5.15 eV and 5.69 eV to 3.63 eV and 4.50 eV as rubrene doping ratio was increased from 0 to 0.4 wt%, respectively. The refractive index dispersion region was explained using the single oscillator (Wemple–DiDomenico) model. The extracted values of dispersion energy (Ed), dielectric constant at infinite frequency (ε∞) and lattice dielectric constant (εL) of PVA/rubrene composite films increased from 0.74 eV, 1.31 and 1.35 to 5.35 eV, 3.47 and 4.35; respectively, whereas oscillator energy (Eo) decreased from 2.41eV to 2.17 eV as rubrene contents increased from 0 to 0.4 wt%, respectively. Indeed, these changes in values of dispersion parameters is evidence to the cross-linking bonds between the host polymer and the rubrene dopants. The improvement of optical properties of PVA/rubrene films demonstrates their applicability as eco-friendly packaging materials, particularly in flexible optoelectronic and microelectronic devices.
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•PVA/rubrene composite films were synthesized using a casting method.•The addition of rubrene dopants in the PVA polymer leads to a decrease in the diffraction peak intensities in XRD spectra.•The estimated values of the band gap decrease with the increase of rubrene content.•The refractive index dispersion was explained using the single oscillator (Wemple– Didomenico) model.•The prepared films can be used as eco-friendly transparent packaging materials for a variety of microelectronic devices.
W-type BaSr Co2 hexaferrites doped with Mn and Ti of the following composition Ba0.5Sr0.5Co2MnxTixFe16-2xO27 (x = 0.00, 0.50, 1.00, 1.50, 2.00, 2.50) were synthesized by sol-gel auto ignition method. ...The structure, phase, spectral bands, microstructure, and magnetic behaviors of the MnTi doped BaSr Co2 W-type ferrites were determined using XRD, FTIR, FESEM, and VSM respectively. Structural and physical parameters such as lattice parameters ‘a’ and ‘c’, crystallite size, cell volume, micro strain, porosity, bulk and X-ray density of the MnTi doped BaSr Co2 W-type hexaferrites were evaluated. The detailed and refined structural properties were determined using the Rietveld refinement of the MnTi doped BaSr Co2 W-type hexagonal ferrites. MAUD software was used for the refinement of the MnTi doped BaSr Co2 W-type hexagonal ferrites patterns. Rb, Rwp and Rexp values were found in the range of 10–19 for MnTi doped BaSr Co2 W-type hexagonal ferrites. The force constants at respective sites were also investigated through FTIR studies. FESEM images showed the hexagonal shape of the MnTi doped hexaferrites. Magnetic properties were estimated from the hysteresis loops recorded by VSM. The magnetic properties were decreased with the MnTi doping. However, anisotropic field was also found to be decreased with MnTi doping. This might be due to the ionic radii and nonmagnetic substitution of Ti in BaSr Co2 W-type hexagonal ferrites. The low coercivity values of these ferrites suggest the use of MnTi doped BaSr Co2 W-type ferrites for microwave absorption, memory devices and magnetic radar absorbing materials (MRAMs) in high frequency regime.
Nanocomposite films of polyethylene oxide/carboxymethyl cellulose (PEO/CMC)/barium titanate (BaTiO3) were prepared using the solution casting technique. The results of X-ray diffraction (XRD) ...analysis depicted the semicrystalline nature of PEO/CMC, which was largely reduced due to BaTiO3 loading. Fourier transform infrared (FT-IR) spectroscopy showed the interaction between the components of blend, PEO and CMC, through the formation of hydrogen bond and confirmed the interaction between BaTiO3 and the functional groups of PEO/CMC, in particular C-O-C for PEO and COO− for CMC. From the Ultraviolet/visible (UV/vis.) absorption spectra, the sharp absorption edge in the UV range for the filled samples was red shifted and the optical energy gap was also calculated. The effect of BaTiO3 on the glass transition, melting point, and decomposition temperatures of the prepared samples was investigated using differential scanning calorimetry (DSC) technique. From the AC conductivity results, the electrical properties were improved depending on temperatures, frequencies, and the BaTiO3 content within the polymeric matrix. This indicated the presence of charge carriers that transported within defect sites by hopping. Furthermore, the mechanism for AC conduction and its dielectric parameters had been studied. Transmission electron micrographs revealed the cubic shape for BaTiO3 with an average size range of 15–50 nm. These observations indicate that these nanocomposite samples are potential candidates in various industrial applications, such as pyroelectric sensors and electromechanical transducers, and in ceramic capacitors as a dielectric material inserted between the two electrodes.
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Transition metal oxides are essential in environmental remediation applications due to their excellent ability to generate charge carriers, i.e. electrons and holes. Bimetallic oxide BiSbO4 (bismuth ...antimonate) possesses unique structure, vigorous oxidation ability and good chemical stability to be used as photocatalyst for the degradation of environmental pollutants. In this report, BiSbO4 and Ag–BiSbO4 (silver doped bismuth antimonate) have successfully synthesized via a simple ultrasonication method. The techniques used for the confirmation of structure, morphology, and vibrational modes for the synthesized material were X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR) spectroscopy. XRD showed that the prepared photocatalyst has a monoclinic structure. At the same time, SEM images presented the flake-like morphology of the as-prepared samples. For the photocatalytic study of prepared samples, methylene blue (MB) was used as a model dye to know the photocatalyst activity. The degradation efficiency of both doped and undoped bismuth antimonate was evaluated and compared. The obtained results showed that the Ag–BiSbO4 exhibited better efficiency than undoped BiSbO4. The methylene blue was degraded up to 85% in the presence of Ag–BiSbO4, while the BiSbO4 showed 70% degradation of methylene blue.
•Successful Synthesis of La doped BiFeO3 nanoparticles.•Potential electrode-materials for supercapacitor applications.•The bandgap engineering of La doping BiFeO3 nanoparticles.•Study pf electronic ...structural modification in La doped BiFeO3 nanoparticles.•The Rietveld refinement of XRD patterns of La doped BiFeO3 nanoparticles.
We investigated the effect of La substitutional ions on the structural, optical, and electrochemical properties of bismuth ferrite (BiFeO3) and used them as electrode materials for high performance supercapacitors. The compositions of 1.05Bi1-xLaxFeO3 (0.0 < x <0.10) nanoparticles were prepared through sol-gel conventional route and denoted as 1.05BiFeO3: BF0; 1.05Bi0.95La0.05FeO3: BF5; 1.05Bi0.90La0.10FeO3: BF10. The Rietveld refinement results of XRD patterns suggested the formation of rhombohedrally distorted perovskite structure (space group: R3c) with negligible secondary phase. The crystallite sizes determined using Scherrer’s formula were found to be in the 59−48 nm range and observed to decrease with an increase in La content. The bandgap measured using UV absorption spectroscopy was found to decrease with an increase in La content in BiFeO3. The SEM micrographs revealed that the prepared samples were composed of nanocrystalline grains with particle sizes ranging from 25 to 40 nm. The electronic structural modification has been confirmed by the XAS analysis of Fe L3,2 and O K edge spectra as a result of La doping. Electrochemical measurements showed that 5% La-doped BFO (BF5) as an electrode demonstrated excellent performance for supercapacitors with a specific capacitance of 328 F g−1 measured with a scan rate of 10 mV s−1. It also exhibited tremendous cyclic stability with capacitance retention of >97 % for 1000 cycles measured at 1A g−1.
In the present work, we have synthesized manganese oxide (Mn3O4) nanoparticles (NPs) using the facile hydrothermal route at different pH (9, 10. 11). The effect of the pH variation on the structural ...and electrochemical properties of the synthesized Mn3O4 NPs have studied. Synthesized NPs are characterized using XRD, SEM, EDS, TEM, BET, cyclic voltammetry, galvanic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) for various properties. The preferred orientation of Mn3O4 growth is along the (211) plane with granule-like morphology. The Mn3O4 electrodes were fabricated and investigated for electrochemical characterizations. The capacitance of the Mn3O4 electrode was calculated from cyclic voltammetry (CV) and galvanometric charge-discharge curves at different scan rates and current densities, respectively. The specific capacitance values of the Mn3O4 electrode (pH 11) were estimated from CV and GCD viz 277 F/g and 262 F/g, respectively, with the higher capacitance retention. Charge transfer resistance was calculated from electrochemical impedance spectroscopy (EIS) measurements. The equivalent series resistance for Mn3O4 at pH 11 is around 0.015 Ω. Nanostructured MnO2 electrodes can be the potential materials for supercapacitor application.
Cobalt sulfide is deemed a promising anode material, owing to its high theoretical capacity (630 mAh g−1). Due to its low conductivity, fast energy decay, and the huge volume change during the ...lithiation process limits its practical application. In this work, a simple and large‐scale method are developed to prepare Co1‐xS nanoparticles embedding in N‐doped carbon/graphene (CSCG). At a current density of 0.2 C, the reversible discharge capacity of CSCG maintains 937 mAh g−1 after 200 cycles. The discharge capacity of CSCG maintains at 596 mAh g−1 after 500 cycles at the high current density of 2.0 C. The excellent performance of CSCG is due to its unique structural features. The addition of rGO buffered volume changes while preventing Co1‐xS from crushing/aggregating during the cycle, resulting in multiplier charge–discharge and long cycle life. The N‐doped carbon provides a simple and easy way to achieve excellent performance in practical applications. Combined with density functional theory calculation, the presence of Co‐vacancies(Co1‐x) increases more active site. Moreover, N‐doping carbon is beneficial to the improve adsorption energy. This work presents a simple and effective structural engineering strategy and also provides a new idea to improve the performance of Li‐ion batteries.
This study presents a simple, large‐scale method for crafting Co1‐xS nanoparticles embedded in N‐doped carbon/graphene (CSCG). The outstanding CSCG performance arises from unique structural features. The addition of rGO buffers volume changes, preventing Co1‐xS crushing/aggregation, and ensuring prolonged cycle life. Combined with density functional theory calculation, Co‐vacancies increase active sites, and N‐doping improves adsorption energy. This work introduces an effective structural engineering strategy.
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•The Mn-Zn ferrite NP’s were synthesized by chemical co-precipitation method.•The crystallite size decreases after zinc substitution.•The IR bands shifted to higher frequency regions ...after zinc substitution.•The optical bandgap energy increased after zinc substitution.•The crystallite size and bandgap values found inversely proportional to each other.
Zinc substituted manganese ferrite Mn1-xZnxFe2O4(x = 0.00, 0.20, 0.40, 0.60, 0.80, 1.00) magnetic nanoparticles were synthesized using low cost and environmental friendly co-precipitation method. The structural, infrared and optical properties of synthesized material were characterized by XRD, TEM, FTIR, EDX and UV–Vis spectroscopy respectively. The XRD result confirmed the formation of good crystallization with a single-phase cubic spinel structure and Fd3m space group. Also determined crystallite size decreases from (20–10 nm). The FTIR spectra confirmed the formation of ferrite phase and tetrahedral and octahedral vibrations. The UV–Vis spectroscopy determines the direct energy bandgap which increases from ~2.26 to ~2.63 eV.
