Borides of several heavy transition metals have been synthesized by arc melting at ambient pressure. The materials are characterized by either low compressibility or high hardness, some of them ...showing a good compromise between both properties. The structure–property relationship is revealed based on their crystal structures and a chemical bonding analysis by means of the electron localization function.
Aluminum based metal matrix composites (AMMCs) have the potential for replacing conventional monolithic materials due to excellent fatigue, creep and wear resistance, high temperature retention, and ...high strength to weight ratio. Thus Aluminum based metal matrix composites have several applications in different industries including Aerospace and Automotive. This study revealed that Al 6063 based metal matrix composites reinforced with Al2O3, SiC, TiO2 have higher hardness, tensile strength, and yield strength as compared to the pure Al 6063. This study shows that hardness, tensile strength, and yield strength are increasing as increasing SiC particles content. Microstructure and surface morphological studies have been carried out to see their surface and particles distribution. Energy Dispersive X-ray Spectroscopy (EDS) and XRD analysis have been conducted to identify elements content. Fourier Transform Infrared Spectroscopy (FTIR) analysis is carried out to identify chemical functional group of the Al6063 metal matrix composites.
This study details the effective solution combustion synthesis of novel Na1−xZr2Dyx(PO4)3(x=0.05−0.5) (hereby abbreviated as NaZrPO:Dy3+) phosphor. The structural investigation of synthesized ...phosphor employing X-ray diffraction and FTIR spectroscopy reveals the formation of single-phase phosphor and the presence of (PO4)3- group. The lattice parameters turned out to be a=b=8.798Å,c=22.794Å. The morphological and chemical analysis is characterized by FE-SEM and X-ray photoelectron spectroscopy, respectively. According to PL spectrum, three traditional emission bands of Dy3+ ions (482 nm, 574 nm, and 663 nm) are observed, and the concentration quenching of the Dy3+ ions in the phosphor occurred at 3 mol. % as a result of the dipole-dipole interaction. Photometric results reveal the emission of the synthesized phosphor in the yellow-whitish region with a color purity of ∼80%. The optical parameters obtained from diffuse-reflectance spectroscopy, such as refractive index, metallization criterion, and bandgap, for the optimal molar concentration (3 mol. %) are 2.109, 0.46, and 4.3 eV, respectively. According to these results, when stimulated by a source of n-UV (348 nm), the synthesized phosphor is a promising candidate for solid-state lighting applications and might be used to produce WLEDs.
Green synthesis of silver nanoparticles was successfully done using Cleome viscosa plant extract, simple, rapid, eco-friendly and a cheaper method. In this study, we used C. viscosa extract for ...synthesizing silver nanoparticles which reduces silver nitrate into silver ions. The obtained AgNPs were characterized by UV, FTIR, XRD, FESEM-EDAX and TEM analysis. They were also analyzed for their biological activities. The presence of biosynthesized AgNPs (410–430 nm) was confirmed by UV–visible spectroscopy and also crystal nature of AgNPs confirmed through XRD analysis; FT-IR spectrum was used to confirm the presence of different functional groups in the biomolecules which act as a capping agent for the nanoparticles. The morphology of AgNPs was analyzed using SEM and the presence of silver was confirmed through elemental analysis. The size of the nanoparticles was in the range of 20–50 nm determined by TEM. The green synthesized AgNPs exhibited a good antibacterial activity against both Gram negative and Gram positive bacteria. Furthermore, the green synthesized AgNPs showed reliable anticancer activity on the lung (A549) and ovarian (PA1) cancer cell lines.
V
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nanoparticles were prepared by ultrasound-assisted method and characterized using XRD, FTIR, SEM, and TEM. XRD pattern revealed an orthorhombic V
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phase with an average crystallite size ...of 52 nm. FTIR spectrum indicated stretching vibration of V-O-V at 430 cm
−1
. The morphology of nanoparticles was determined by SEM and TEM analysis. The optical bandgap of V
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nanoparticles was found to be 2.4 eV. The photocatalytic degradation study of V
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nanoparticles was investigated against the Rose Bengal (RB) dye under solar light irradiation. Ultrasound-assisted V
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nanoparticles showed an excellent photocatalytic activity (RB dye). The antibacterial activity (disc diffusion method) of ultrasound-assisted V
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nanoparticles was studied against human pathogenic bacteria (S.aureus, E.coli, P.aeruginosa and P. Vulgaris). The results obtained indicate that the prepared nanoparticles will be useful in dye degradation and biomedical applications.
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•WS2/SnS2 composite thin films were study for photo response.•Composite thin films deposited via low cost CBD Method.•Composite WS2/SnS2 thin films shows detectivity ∼ 1013 in Jones.
...The composite WS2/SnS2 thin films deposited by CBD have been studied for variations in deposition time and sulfur concentration. XRD results show a polycrystalline hexagonal phase with crystallite size varying from ∼ 3.56 nm to ∼ 16.35 nm in composite thin films. The optical absorption spectra of S-2 show maximum absorption peaks in 380 nm to 800 nm. The band gap was calculated to be ∼ 1.52 eV to ∼ 2.5 eV. We measured the current–voltage characteristics across the junction to determine the transport properties. A photodetector application involving the WS2/SnS2 composite structure shows a maximum specific detectivity of 6.2 x 1013 Jones. The reason for varying the electrical parameters discussed in this work.
Perovskite-type oxides have gained significant attention in the scientific community due to their unique properties and potential applications. Their ability to exsolve reducible B-site cations (e.g. ...Co, Ni, Cu) combined with their flexibility regarding A-site and B-site composition allows for the tailoring of novel catalytic materials. This study focuses on B-site doped perovskite-type oxides with a general formula of Nd0.6Ca0.4Fe1-xCuxO3 and Pr0.6Ca0.4Fe1-xCuxO3 (x = 0.0, 0.03, 0.05, 0.10) for potential use as a catalyst for Methanol Steam Reforming via the exsolution of catalytically active Cu nanoparticles. The atomic and electronic structure, morphology, and exsolution behaviour of these materials were investigated experimentally and with density functional theory, with a specific emphasis on the impact of B-site doping with varying Cu content as well as choice of A-site element. Both parameters influenced the crystal structure, surface area, and morphology of the materials. The exsolution behaviour of the materials was observed using in-situ XRD at DESY beamline P02.1 at PETRA III, with nanoparticles forming after reductive treatments on the host oxide surface. The quantity and size of the nanoparticles were found to be adjustable by selecting the A-site ion, doping content at the B-site, and the choice of reducing agent. Materials with higher Cu content on the B-site exhibited facilitated exsolution. Furthermore, exsolution was promoted with Nd as the A-site element compared to Pr. In conclusion, the controlled exsolution of Cu nanoparticles introduces Cu-doped perovskite-type oxides as promising candidates for developing novel catalytic systems. The findings underscore the importance of fine-tuning the oxide composition (A-site element, amount of B-site dopant) to achieve tailored exsolution of nanoparticles, which is crucial for rational material design. By leveraging this knowledge, catalysts with finely tuned properties can be created for specific applications and operational environments.
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•Nanoparticle exsolution on Nd and Pr perovskites verified by synchrotron XRD.•Cu-doping found to improve exsolution.•Number and size of nanoparticles adjustable by catalyst design.•DFT confirms influence of A- and B-site doping.
The magnesium oxide (MgO) nanoparticles were synthesised by solution combustion method. XRD results confirm the nanophase (crystallite size ∼30 nm) of a prepared sample with cubic structure. ...Mechanical stability assessments indicated excellent elastic moduli, highlighting the brittle nature of a material. Scanning Electron Microscopy (SEM) revealed the agglomerated and porous morphology of the MgO nanoparticles. UV–Visible characterization reveals an absorption peak at 295 nm, corresponding to an optical band gap of 3.6 eV. Photoluminescence spectroscopy identifies emission peaks at 406 nm, 436 nm, and 450 nm attributed to various structural defects. The frequency and temperature dependence on AC electrical properties were investigated at varying temperature (27oC–250oC) and frequency (50 Hz-5 MHz). The electrical modulus and Cole-Cole plots reveal relaxational behaviour and changes in the material's stiffness with temperature. From the obtained results it is evident that the synthesised MgO nanoparticles are suitable for electronic device applications.
•Synthesis of MgO nanoparticles via solution combustion method yielding cubic crystal structure.•Structural and elastic analysis indicates anisotropic elastic properties and ductile nature.•UV–Vis spectroscopy identifies a significant absorption peak at 295 nm, unveiling an optical bandgap of 3.6 eV.•Dielectric analysis at different temperatures reveals conventional behavior with temperature and frequency variations.•AC conductivity analysis reveals Jonscher's power law behavior, showcasing frequency-dependent conductivity.
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