Nickel ferrites (NF), silver doped nickel ferrites (AgNF), and a composite of silver doped nickel ferrites with reduced graphene oxide (AgNF@rGO) were prepared through the co-precipitation method. ...The X-ray diffraction analysis was carried out to confirm the structure of prepared materials, and the crystallite size of prepared ferrites was less than 10 nm. FT-IR spectroscopy was performed for the confirmation of functional groups present in the synthesized materials. The surface morphology of prepared samples was investigated via scanning electron microscopy. Optical analysis was carried out with the help of UV–Visible spectroscopy. Thermogravimetric analysis was performed to check the thermal stability. The photocatalytic degradation of methylene blue under solar light irradiation was studied. The AgNF@rGO composite showed 76% degradation of coloured compound (methylene blue) and 50% degradation of colourless compound (benzimidazole). The enhanced photocatalytic degradation efficacy of AgNF@rGO was ascribed to the reduced graphene oxide sheets, which provided a large surface area and the ability to trap electrons from the conduction band. As a result, the decreased recombination rate of electrons and holes enhanced the degradation ability of the composite based photocatalyst. A scavenging experiment was also performed to determine the most photoactive species taking part in the degradation process. In comparison among all prepared samples, AgNF@rGO showed the maximum photocatalytic activity. It was because of the large surface area of the AgNF@rGO. It was investigated that AgNF@rGO is the most effective catalyst for the degradation of coloured and colourless organic pollutants.
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The present work, novel growth of ternary CuO-Fe3O4/g-C3N4 nanocomposites (NCs) with three different ratio (CuO-Fe3O4:g-C3N4 = 90:10; 75:25 and 50:50), binary CuO-Fe3O4 nanocomposite (NC) and its ...pristine g-C3N4, CuO and Fe3O4 was synthesized and characterized by XRD, SEM with EDX, TEM, Raman, XPS, UV-DRS and PL. The XRD pattern exhibited the diffraction peaks of g-C3N4 (hexagonal) and CuO (monoclinic) and Fe3O4 (FCC) and the CuO-Fe3O4 mixing of monoclinic and cubic phases along with CuO (−111) direction. The TEM analysis shows the dispersion of CuO-Fe3O4 on g-C3N4 sheets in the CuO-Fe3O4/g-C3N4 (50:50) NC. From the XPS spectra, the oxidation states of Cu2p, Fe2p, O1s, C1s, and N1s, as well as their orbital bonding, are analyzed. The bandgap was calculated by photon energy vs ILD and (F(R∞)hv)2 by using UV-DRS spectrum. The catalyst, CuO-Fe3O4/g-C3N4 (50:50)@NF had a low overpotential of 69 mV at the current density of 10 mA cm2, close to the value of 20 % Pt (45 mV). A chronoamperometry test demonstrated that CuO-Fe3O4/g-C3N4 (50:50)@NF works efficiently for more than 30 h at a high current density of 15 mA cm−2 indicating the strong stability of CuO-Fe3O4/g-C3N4 (50:50)@NF. The maximum photocatalytic degradation efficiency against Rhodamine-B was found to be 99.51 % and crystal violet degradation efficiency is 98.02 % by using CuO-Fe3O4/g-C3N4 (50:50).
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•A novel Dy3+doped MgP2O6 phosphor is synthesized via combustion route.•The Rietveld refinement method is used to calculate the lattice parameters.•Photometric results shows the emission profile in ...yellow-whitish region.•The synthesized phosphor is a potential candidate for WLED applications.
A yellowish white light emitting Dy3+ (0.5, 1, 1.5, 2, and 2.5 mole%) activated MgP2O6 phosphors were prepared using Solution combustion (SC) method. The X-ray diffraction (XRD) and Rietveld refinement confirmed the phase purity with “monoclinic symmetry” having space group P21/n. The lattice constant of the optimum doped sample is also refined by “Full Prof software”. Photoluminescence (PL) spectroscopy was employed to observe the luminescent properties, including both excitation and emission features. The phosphor verified intense yellowish emission at 573 nm, analogous to the hypersensitive electric dipole transition4F9/2→6H13/2. The critical activated concentration of MgP2O6:Dy3+ phosphor approximately occurs at 1.5 mole%. The phosphor exhibits conventional applications in solid-state lighting when excited under UV light at 348 nm.
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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
2
O
5
nanoparticles were prepared by ultrasound-assisted method and characterized using XRD, FTIR, SEM, and TEM. XRD pattern revealed an orthorhombic V
2
O
5
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
2
O
5
nanoparticles was found to be 2.4 eV. The photocatalytic degradation study of V
2
O
5
nanoparticles was investigated against the Rose Bengal (RB) dye under solar light irradiation. Ultrasound-assisted V
2
O
5
nanoparticles showed an excellent photocatalytic activity (RB dye). The antibacterial activity (disc diffusion method) of ultrasound-assisted V
2
O
5
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.
Molybdenum disulfide (MoS
) has been considered to be a promising anode material for sodium ion batteries (SIBs), because of its high capacity and graphene-like layered structure. However, ...irreversible conversion reaction during the sodiation/desodiation process is a major problem that must be overcome before its practical applications. In this work, MoS
/amorphous carbon (C) microtubes (MTs) composed of heterostructured MoS
/C nanosheets have been developed via a simple template method. The existence of MoS
/C heterointerface plays a key role in achieving high and stable performance by stabilizing the reaction products Mo and sulfide phases, providing fast electronic and Na
ions diffusion mobility, and alleviating the volume change. MoS
/C MTs exhibit a high reversible specific capacity of 563.5 mA h g
at 0.2 A g
, good rate performance (520.5, 489.4, 452.9, 425.1, and 401.3 mA h g
at 0.5, 1.0, 2.0, 5.0, and 10.0 A g
, respectively), and excellent cycling stability (484.9 mA h g
at 2.0 A g
after 1500 cycles).
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