Mean Crystallite Size Research Articles

Structural and electrical characterization of nickel sulfide nanoparticles

Nickel sulfide nanoparticles were successfully synthesized through a meticulous process involving a well-mixed powder of Ni(CH3COO)2∙2H2O and Thiourea. The X-ray diffraction analysis provided insights into the structural nature of NiS, revealing its polycrystalline characteristics with a hexagonal system. This information is fundamental, as it forms the basis for understanding the material’s behavior and functionality in various applications. Determining the average values of mean crystallite size, microstrain, and dislocation Nickel sulfide nanoparticles were successfully synthesized through a careful process involving a well-mixed powder of Ni(II)2∙2H2O and Thiourea. The X-ray diffraction analysis provided insights into the structural nature of NiS, revealing its polycrystalline characteristics with a hexagonal system. This information is crucial as it forms the basis for understanding the material’s behavior and functionality in various applications. Determining the average values of mean crystallite size, microstrain, and dislocation density for the (100) plane (32.62 nm, 0.000296, and 0.000939 nm-2, respectively) contributes to a comprehensive understanding of the material’s structural features. The photoluminescence spectrum of NiS in the visible region revealed split peaks at 405.8 and 428.25 nm, shedding light on the radiative recombination process between electrons and holes. The confirmation of thermal stability through a thermogravimetry diagram is essential for applications in elevated temperature environments, ensuring the material’s reliability under varying conditions. Analyzing the stoichiometry of NiS using energy dispersive spectroscopy attached to transmission electron microscopy provides insights into the material’s composition. Cyclic voltammetry results indicating a diffusion coefficient greater than that of NiS added to carbon hold significance for electrochemical applications. The unique characteristic peaks observed in cyclic voltammetry for fuel cell applications suggest the potential use of NiS in energy conversion technologies, broadening its scope of application. The confirmation of NiS’s ability to elucidate the physical and electronic properties of electrochemical systems through electrochemical impedance spectroscopy underlines its importance as a versatile material in various research and practical domains.

Green synthesis of Z-scheme CeO2 decorated ZnO nanocomposites for photodegradation of organic pollutants, antioxidant activity and its effects on seed germination

The present work aimed to report a green synthesis of CeO2@ZnO nanocomposites via co-precipitation method using azadirachta indica aqueous leaf extract. The characterization of the prepared CeO2@ZnO nanocomposites were done using XRD, FTIR, SEM, EDAX, UV–vis, and PL techniques to examine the structural properties, functional group, morphological and electronic properties. As prepared CeO2@ZnO nanocomposites have been used for photo degradation of Crystal Violet (CV), Methylene blue (MB) and Rhodamine B (RhB) dyes in presence of solar light in aqueous solution. From structural analysis the mean crystallite sizes of the synthesized nanocomposites varied from 27 nm to 9 nm. The degradation of MB, CV and RhB dyes follows pseudo-first order reaction rate with the rate constantsk1 for MB is 10.09 × 10−3 min−1, k1 for CV is 8.71 × 10−3 min−1, k1 for RhB is 0.92 × 10−3 min−1.The characterized nanocomposites were used for seedling growth, physiological and biochemical responses during seed germination. In CeO2@ZnO nanocomposites treatments, significantly higher values of shoot length and root length were observed in CZ1 (0.5, and 1 mg/ml) treated seedlings as compared to other samples. Similarly, the activities of ɑ-amylase and protease enzymes were recorded to be maximum for CZ1 nanocomposites. For instance, the increased activity of α-amylase was observed to be 2.12, 2.09, and 1.33 folds higher in CZ1, CZ2, and CZ3 (1 mg/ml) treated seedlings as compared to the control. Similarly, the protease activity was reported to be increased by 0.011 folds in CZ1 nanocomposites (1 mg/ml) treated seedlings as compared to the control. Furthermore, all the CeO2@ZnOnanocomposites have excellent DPPH, and ABTS free radical scavenging activities, confirmed by the Ferric-Reducing Antioxidant Power (FRAP) assay. The CZ1 nanocomposites showed the best results. The CeO2@ZnO nanocomposites were found to have no toxic effects on cellular division confirmed with improved mitotic index under different treatment regimens.

Synthesis of Silver Nanoparticles Using Plant Extracts from Legeneraria Siceraria Fruits and Assessment of their Anti-Bacterial and Anti-Oxidant Activities

Nanotechnology is a key subject of science, engineering, and technology that is experiencing enormous growth in the current century. In this study, fruits of the legeneraria siceraria plant, this is widely used in traditional medicines in Ethiopian rural areas, used as reducing and capping agent for AgNPs synthesis. The legeneraria siceraria fruits -mediated synthesized AgNPs characterized by ultravioletvisible (UV-VIS.) spectrophotometry, Fourier transform-infrared (FT-IR) spectroscopy, X-ray diffractometer (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS). The optimal synthesization parameters for AgNPs in this study were temperature 60 °C, stirring time 60 minutes, pH 11, and 2 mM silver nitrate concentration. Characteristic and well-defined SPR bands for AgNPs were confirmed at around λmax = 426 nm. Synthesized AgNPs of calculated mean crystallite size were 10.21 nm. Scanning electron microscopy (SEM) revealed the synthesized AgNPs have a spherical structure. The antibacterial activity of AgNPs synthesized using legeneraria siceraria fruits medicinal plants demonstrated that Gram-positive and Gram-negative bacteria inhibited. Additionally, the AgNPs showed minimal toxicity to human cells. AgNPs were useful antioxidants for health preservation against different oxidative stress associated with degenerative diseases. In this work, it acts at scavenging against DPPH.

Proflavine binding to La-Sr perovskite manganite nanoparticles at temperatures above and below the Сurie temperature

The magnetic properties of La1-xSrxMnO3 (LSMO) nanoparticles within the ferromagnetic region (x ≈ 0.2–0.5) enable their application in two types of cancer treatment: chemotherapy drug delivery and self-controlled hyperthermia. Single-phase La0.80Sr0.20MnO3 nanoparticles were prepared by the sol-gel process followed by mechanical processing. Sample characterization was performed by using XRD, TEM, EPR, and DLS techniques. The encapsulation efficiency of proflavine to the nanoparticles was determined via spectrophotometry. The mean size of crystallites of LSMO nanoparticles is 18 nm, and the Curie temperature is 319 K. Bare LSMO particles do not form a colloidally stable aqueous suspension; they exhibit a zeta potential close to zero and provide micro-sized aggregates. Application of sodium citrate for their stabilization leads to a decrease in the size of agglomerates and to a highly negative zeta potential of –33 mV. The efficiency of proflavine sorption by LSMO nanoparticles increases significantly above the Curie temperature, from 16.1 % at 298 K to 26.2 % at 333 K. This increase is attributed to the partial disruption of nanoparticle agglomerates in suspension after the LSMO phase loses its ferromagnetic order. In summary, heating LSMO nanoparticles above the Curie temperature increases the degree of drug loading on the nanoparticles.

High Milling Time Influence on the Phase Stability and Electrical Properties of Fe50Mn35Sn15 Heusler Alloy Obtained by Mechanical Alloying.

Fe50Mn35Sn15 Heusler alloy, obtained by mechanical alloying, was subjected to larger milling times in the range of 30-50 h to study the phase stability and morphology. X-ray diffraction studies have shown that the milled samples crystallise in a disordered A2 structure. The A2 structure was found to be stable in the milling range studied, contrary to the computation studies performed on this composition. Using Rietveld refinements, the lattice parameter, mean crystallite size, and lattice strain were computed. The nature of the obtained phases by milling was found to be nanocrystalline with values below 50 nm. A linear increase rate of 0.00713 (h-1) was computed for lattice strain as the milling time increased. As the milling time increases, the lattice parameter of the cubic Heusler was found to have a decreasing behaviour, reaching 2.9517 Å at 50 h of milling. The morphological and elemental distribution-characterised by scanning electron microscopy and energy-dispersive X-ray spectroscopy-evidenced Mn and Sn phase clustering. As the milling time increased, the morphology of the sample was found to change. The Mn and Sn cluster size was quantified by elemental line profile. Electrical resistivity evolution with milling time was analysed, showing a peak for 40 h of milling time.

Investigating the physicochemical, optical and microstructural properties of sodium doped CdO nano powders fabricated by co-precipitation technique for blue emission and antimicrobial applications

A series of cubic structured pristine and sodium doped CdO nanoparticles (Cd1-xNaxO NPs) with varying dopant concentrations have been synthesized using simple Co-precipitation process. Crystal structure and the connection between various structural parameters are evidenced using powder XRD diffractograms. The crystallite size is evaluated with different models and the mean crystallite size was reduced with Na ions doping concentration due to severe lattice distortion. The existence of various vibrational modes and functional groups were demonstrated through FTIR characterization. The signature of Cd–O and Na–O stretching modes were confirmed with FTIR. Raman spectra also confirmed the formation of metal–oxygen bond and the second order vibration features. The direct bandgap of the CdO material increased from 2.132 to 2.40 eV with an increase in the Na dopant content which presents the appearance of a blue shift as probed through UV–Vis spectroscopy. The surface morphology and microstructure of the samples were studied using FESEM and HRTEM images, respectively. EDAX measurements revealed the presence of Cd, and O in the host lattice and Cd, O and Na in the doped CdO constructions. The SAED concentric ring pattern of Cd1-xNaxO nanoparticles demonstrated the polycrystalline nature of the samples. PL study revealed the impression of intrinsic defects and the photoluminescence colour emission of the Cd1-xNaxO materials shifted more towards bright blue region as the Na doping concentration increased. CIE color coordinates of Na-doped CdO NPs shows intense bluish color and extending its applications in commercial UV lighting, blue LEDs and Fluorescent biological labelling and tagging. Cd1-xNaxO nanoparticles exhibited enhanced antibacterial activity with increasing Na doping content towards gram-positive, and gram-negative bacteria. Further, the antifungal analysis against C. albicans, and A. niger authenticate that Na+ substituted CdO nanoparticles shows excellent antifungal activity. The mechanism of the above observed results is examined in detail in this article.

Synthesis and Characterizations of BiFeO3 Nanoparticles for Photocatalytic Application

AbstractBismuth ferrite (BiFeO3) nanoparticles were synthesized using sol‐gel method and annealed at 450 °C, 550 °C, 650 °C, and 750 °C for 2 hours. The role of annealing temperature on structural, optical, magnetic, and dielectric properties of BiFeO3 nanoparticles was studied. XRD patterns of BiFeO3 nanoparticles confirm the rhombohedral structure with a mean crystallite size of 40 nm. The optical bandgap of the BiFeO3 nanoparticles increased from 1.9 eV to 2.02 eV with annealing temperature. From photoluminescence spectra, it was observed that the BiFeO3 nanoparticles showed a clear emission peak at 565 nm and its intensity decreased with annealing temperature. Magnetic properties of the BiFeO3 nanoparticles were studied at room temperature and different magnetic behaviours were found in BiFeO3 nanoparticles. The BiFeO3 nanoparticles exhibited ferromagnetism at low annealing temperatures and diamagnetic nature at high annealing temperatures. The AC conductivity studies showed that BiFeO3 nanoparticles possess a dielectric constant of 170 with the least dielectric loss. The BiFeO3 nanoparticles annealed at 750 °C were studied for photocatalytic properties and showed good photocatalytic activity in the visible region. A prominent absorption peak at 663 nm in absorption spectra due to MB and it confirm the utility of BFO as photocatalyst applications.

High-entropy oxide (CeGdHfPrZr)O2 nanoparticles as reusable photocatalyst for wastewater remediation

High-entropy materials (HEM) play a significant role in current scientific research and are characterized by their complexity, which makes them the next generation nanomaterials. The present study investigates the synthesis of (CeGdHfPrZr)O2 high-entropy oxide nanoparticles using a hydrothermal technique. Various characterization techniques, such as X-ray diffraction (XRD), and scanning electron microscopy (SEM) were used to investigate the structural properties, while UV-visible spectroscopy was used to investigate the optical properties. The results indicate the formation of a single-phase cubic fluorite high-entropy oxide system with a mean crystallite size of 5.4 nm. The optical bandgap of (CeGdHfPrZr)O2 nanoparticles is found to be 2.01 eV. The photocatalytic activity of the synthesized oxide nanoparticles was assessed using methylene blue (MB) dye as a model pollutant. In the current study, we examined and discussed the effect of various photocatalytic parameters on the degradation of MB dye. The results showed that the (CeGdHfPrZr)O2 nanoparticles had high photocatalytic activity and were found to be dependent on various parameters. A higher photocatalyst concentration impedes the degradation kinetics and, as a result, limits photon penetration into the reaction solution. Similarly, increased hydroxyl radical generation at a basic pH improved MB dye degradation. In addition, based on the band positions and radical scavenging study, hydroxyl radicals are responsible for the degradation of dye. (CeGdHfPrZr)O2 nanoparticles can be used as a promising catalyst for the photocatalytic degradation of organic pollutants.

Influence of Long Milling Time on the Electrical Resistivity of Nanocrystalline Ni2MnSn Heusler Alloy Obtained by Mechanosynthesis.

A Ni2MnSn Heusler alloy was obtained as a single B2 phase after 12 h of mechanical milling. The influence of prolonged milling on the phase stability was analysed for milling times up to 50 h, related to mean crystallite size, lattice strain, and electrical resistivity. The nature of the powders in the milled range was found to be nanocrystalline, with a mean crystallite size of about 33 ± 2 nm. An evaluation of the internal stresses induced by milling was performed, a linear behaviour was found, and a coefficient of the internal stress increase with milling time was proposed. Particle size distributions of milled samples were analysed, and the morphology of the powders was visualised by scanning electron microscopy. The elemental distribution of milled samples was quantified by energy-dispersive X-ray spectroscopy. Electrical resistivity measurements were performed on compacted samples, and their behaviour with milling time was analysed.

Microstructure and properties of ZrB2-reinforced aluminum matrix composites consolidated by ECAP process

In this research work, the effects of mechanical alloying and subsequent compaction by ECAP on the microstructural, physical, and mechanical properties of Al-ZrB2 metal matrix composites (MMCs) were evaluated. To prepare composite powders, a mixture of Al and ZrB2 particles was mechanically alloyed at various times of 1, 6, 12, 18 and 24 h. SEM micrographs indicate that the size of the obtained particles decreases by increasing the time of mechanical alloying up to 18 h. However, after this time, increasing the time of mechanical alloying has led to an increase in the size of the particles. By means of mechanical alloying for 18 h, the average size of fine particles reached 823 nm, while coarse particles were 8 μm. The calculation via the use of XRD examination implies that the mean crystallite size of powder decreased from about 68 nm to 31 nm and 26.8 nm, for Al and Al-5%ZrB2 samples, respectively, while lattice strain increased from 0.25% to 0.64% and from 0.3% to 0.73% after 1 h to 24 h milling of same samples, respectively. However, the rate of crystallite size reduction after 12 h of mechanical alloying is gradually reduced, and that is reached its lowest level after 18 h. After that, increasing the time of mechanical alloying has led to a saturation in the lattice strain. In continue, the resulting composite powder was heated, consolidated and turned into bulk material by warm equal channel angular pressing (ECAP) at the temperature of 250 °C. The resultant optimum composite has been characterized by EDS elemental mapping. Microhardness measurements and shear punch tests were performed to evaluate the mechanical properties of the unreinforced and composite samples after the ECAP process. The Al-ZrB2 MMC bulk samples subjected to ECAP, with a ZrB2 amount of 5 wt%, had a relative density, hardness, and ultimate shear strength of 99.3%, 170 HV, and 151 MPa, respectively, using powders which have been mechanically alloyed up to 24 h.

Influence of Bi3+ ions on structural, morphology, elemental, vibrational, optical, magnetic, NLO and optical limiting properties of lanthanum ferrites nanoparticles

Nanoparticles of LaFe1-xBixO3 were successfully synthesized through the microwave combustion process (MCP) employing l-alanine as the fuel source. XRD and FT-IR analyses conclusively confirmed the orthorhombic structure of lanthanum ferrite, with the mean crystallite size varying between 56.32 and 25.43 nm. The optical energy gap value, calculated from UV–vis spectra, fell within the range of 1.84 to 2.49 eV. EDX analyses verified the presence of Bi, La, Fe, and O elements. Furthermore, FE-SEM images exhibited the nanoparticles' distinctive aggregated spherical morphology. Notably, VSM analysis showcased the robust diamagnetic behavior of LaFe1-xBixO3 nanoparticles. In photoluminescence's spectra, the samples underwent excitation with a wavelength of 315 nm. The values of Hc (coercivity) and Mr (remanence) fell within the range of 121.98 to 332.39 Oe and 0.1592 to 0.0907 emu/g for LaFe1-xBixO3 respectively. Z-scan experiments yielded values for the nonlinear susceptibility, index of nonlinear refraction, and coefficient of nonlinear absorption. The findings from optical limiting studies serve as additional verification, underscoring the suitability of these materials as promising options for integration into devices, including optical switches and optical power limiters.

Dielectric and magnetic response of mechanically activated Mn-doped SrTiO3 ceramics

This research was focused on the influence of manganese (Mn) incorporation at Sr and/or Ti sites on the microstructure, relative dielectric permittivity and specific magnetization of strontium titanate (SrTiO3) ceramics. A solid-state method was used for the preparation of mechanically activated (10, 30 and 120 min) Mn-doped SrTiO3 ceramics with various manganese dioxide (MnO2) weight percentages (1.5, 3 and 6 wt%). Rietveld's analysis showed that the mean crystallite size in doped-activated SrTiO3 ceramics is smaller than in undoped ceramics, which is a consequence of additional crystal structure distortion due to ion substitution. Changes in the Raman spectra indicated dopant incorporation in the SrTiO3 lattice. The microstructural analysis pointed out a decrease in the mean grain size with increasing dopant concentration and time of activation. The highest values of permittivity and magnetization were observed for Mn-doped SrTiO3 ceramic mechanically activated for 120 min. Based on all the above, the optimal electrical and magnetic properties of SrTiO3 ceramics can be achieved by the appropriate choice of mechanical activation time and dopant concentration.

Modulation of micro-structural, opto-electronic and photo-induced fluorescence properties in sol-gel derived Pb1-xZnxO nanoparticles through the analytical study of vacancy-type defects

In the present work, the doping effect of Zn2+ ion (varying doping concentrations in the range of 0 %–30 %) on PbO nanoparticles (NPs) has been investigated proficiently. This study aims at in-depth analysis of the structure-property relationships of the sol-gel derived Zn doped PbO (Pb1-xZnxO) NPs, especially the vacancy evolved properties and the luminescence properties. The X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), field emission scanning electron microscopy (FESEM) and Fourier-transform infrared (FT-IR) spectroscopic characterization analyses justified the nanocrystallinity of the Pb1-xZnxO powdered NPs while the mean crystallite sizes were located in between 12 and 36 nm range. Williamson – Hall (W – H) method revealed a monotonous increase of the lattice strain which is compatible with the decrease of NPs’ crystallite size by increase in the Zn2+ doping level. The replacement of Pb2+ ions with the Zn2+ ions caused the reduction of crystallite size by the higher Zn2+ doping level. Prominent peaks of Zn, Pb and O elements are noticed in energy dispersive X-ray spectroscopic (EDS) characterization. The elemental distributions of the chemicals present in the NPs were explored by the elemental mapping analysis. The optical absorption (OA) analysis indicated that the energy band gap (Eg) can be estimated to be 2.21, 2.36, 2.55 and 2.70 eV for 0, 10, 20 & 30 % Zn doped PbO NPs, respectively. The positron annihilation lifetime (PAL) spectroscopic studies evidenced the presence of vacancy type defects within the NPs and an increase in defect concentrations has been observed by the increase in Zn concentrations. The photo-induced fluorescence (FL) emission spectra exhibited three luminescence peaks around the wavelengths 430 nm, 490 nm and 522 nm for all the NPs. The observations suggested the possibility of tailoring the characteristics of the synthesized NPs for practical applications in the field of optoelectronics.

Examination of structural and spectrophotometric optical characteristics of nano-like flower quinolinyl carbonyl pyrazole-1-carbodithioate films: a new trend for optoelectronic applications

The current investigation entailed the synthesis of benzyl 5-amino-4-[(1-ethyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)carbonyl]-1H-pyrazole-1-carbodithioate (referred as BAEHQP, compound 2) from 6-ethyl-4,5-dioxo-5,6-dihydro-4H-pyrano[3,2-c]quinoline-3-carbonitrile (compound 1), followed by its characterization in nanocrystalline thin films produced through thermal evaporation in a high vacuum. Computational and experimental methodologies were employed for this purpose. Density functional theory (DFT) calculations using the B3LYP/6-311++G(d,p) basis set were utilized to predict the HOMO-LUMO gap and evaluate the global reactivity descriptors, elucidating the chemical hardness, kinetic stability, and electron-donating capabilities. X-ray diffraction (XRD) analysis verified the presence of a polycrystalline structure in the BAEHQP powder and indicated an amorphous nature in the thin film. Utilizing the Williamson-Hall formula, the mean crystallite size and microstrain were determined to be 63.36 nm and 0.00667, respectively. Scanning electron microscopy corroborated the nanoflower-like structure, and particle size analysis was conducted to determine the size distribution. The optical properties, encompassing both linear and nonlinear aspects, of BAEHQP thin film were investigated using spectrophotometric methods, delineating band transitions and identifying a fundamental direct energy gap of 2.2 eV. The distinct attributes of thin-film absorption and dispersion were outlined, and the unanticipated findings hold potential implications for advancing the industrialization of photodiode device manufacturing.

Improvements of multifunctional spintronic and optoelectronic applications of nanostructured Eu-doped ZnS thin films through magnetic and linear, nonlinear optical investigations

This study describes the spintronic and optoelectronic improvements upon Eu substitution in Zn atomic site of the nanostructure ZnS thin films. The electron beam deposition technique has been used to deposit a series of Zn1-xEuxS thin films on a glass substrate with different Eu dopants (x = 0, 0.01, 0.03, 0.05, and 0.08). The nanostructure nature of the Eu-doped ZnS thin film has been confirmed from structural and morphology studies performed by the X-ray diffraction (XRD) and atomic force microscope (AFM) measurements. XRD investigations further show a hexagonal-type structure with no detectable extra phases with the lattice parameter c increasing, while a decrease linearly with increasing Eu-dopant in the ZnS hosted lattice. The microstructures analysis reveals a reduction in the mean crystallite size and increasing in the lattice strain of the films with rising Eu doping. The Fourier transform infrared spectra display the existence of chemical bonds in the thin films whereas photoluminescence reveals near-band edge emission. The linear optical parameters were obtained from the analysis of the transmission data measured by the spectrophotometer technique. The results reveal that the band gap energy (EgOpt) reduces by raising ohe Eu doping ratio, which is ascribed to the structural deformation (strain and/or defects) confirmed from structural analysis, density of localized states and PL measurements. The index of refraction n was calculated using the Swanepoel method. The values were found to increase as the level of Eu doping grows, which is associated with the rise in polarizability. Wemple and DiDomenico's (WDD) model was utilized to compute the dispersive and oscillator energies (Eo, and Ed), the nonlinear absorption coefficient βc, nonlinear refractive index n2, and nonlinear optical susceptibility χ3. The results demonstrate that the adjustability of EgOpt , Eo, and Ed of ZnS: Eu films is conducted to improve the nonlinear optical characteristics, providing it well-suited for optoelectronic device implementations. On the other hand, ZnS doped with Eu film displays inherent ferromagnetic properties at room temperature, as evidenced by the results of the magnetic investigation. This finding could be attributed to the presence of sulphur defects (vacancies), as supported by photoluminescence (PL) measurements, which lead to the creation of the bound magnetic polaron. These discoveries indicate the potential of utilizing Eu-doped ZnS film in the effective development of spintronic devices.

Effect of lanthanum substitution and annealing temperature on the structural and morphological properties of M-type calcium hexaferrite

To investigate the influence of annealing temperature and lanthanum substitution on the structural properties of M-type calcium hexaferrite, we prepared unsubstituted and lanthanum-substituted Ca1-xLaxFe12O19 (x = 0.3, 0.4 and 0.5) powders by mean of sol–gel auto-combustion procedure, annealed between 800 °C and 1350 °C during 5 h in a rate of 180 °C per hour. XRD analysis showed that the M-type phase does not appear in the unsubstituted samples even with annealing at 1200 °C. The XRD patterns of the substituted samples contained peaks of the M-type phase with the presence of α-Fe2O3 as a secondary phase, the intensity of α-Fe2O3 decreased with increasing annealing temperature between 1200 °C and 1350 °C, and also as a function of lanthanum substitution concentration, which shows that the best lanthanum substitution concentration was x = 0.5. Lattice parameters of synthesized Ca0.5La0.5Fe12O19 align with literature results of various M-type hexaferrite. SEM micrographs of the Ca0.5La0.5Fe12O19 annealed at 1350 °C revealed that the mean and median crystallite size values were calculated to be 4.37 μm and 4.32 μm respectively.

Characterization and antimicrobial Properties of Cotton Fabric Loaded with green Synthesized Silica Nanoparticles

During the past decade, improvement in the functionality of textile materials has become an important research field due to their significant health and safety benefits. Here we report, simple and cost-effective green synthesis of silica nanoparticles from fibrous residue of sugarcane bagasse followed by investigating the applicability on cotton fabric. The characteristics of synthesized nanoparticles were determined by techniques including FTIR (exhibited characteristic peak at 791.01 attributed to vibration of Si-O and the absorption band at 1072.48 cm-1 owing to asymmetric vibration of Si-O-Si confirming the formation of SNPs), SEM (40±2nm), and XRD (Examined spectra with JCPDS 36-1451 indicate well-defined peaks of Silicon Oxide). Debye Scherrer equation was used to calculate the mean crystallite size (19.79 nm) of powder Silica NP sample at the full width half maximum (FWHM) of the diffraction peaks of 2Ɵ positions. Applicability of synthesized nanoparticles was determined by assessing thermal stability and antimicrobial property of treated and untreated cotton fabric. It was observed that silica nanoparticles coated fabric showed substantial thermal stability at 1 % Silica NPs comparatively treated with 2% and 3% silica NPs due to clustering phenomena. Antimicrobial property, confirmatory test as positive control of treated fabric shown substantial increased in antibacterial activity in solutions containing silica NPs as compared to the ethanol solution. Moreover, 76 green profiling score of synthesized method was evaluated by Analytical Eco-Scale tool.

A new phenomenon in a selective laser melted 316L stainless steel with a wider and higher laser energy density

Defects, boundaries, textures, tensile properties, fractographies, sub-grains, nano-oxide particles, and deformation twins in selective laser melted 316L stainless steel (SLM316LSS) were systematically characterized as functions of laser energy density. The defects, boundaries, textures of the as-built SLM316LSS were shown to depend largely on the applied laser power. The porosity of the SLM316LSS significantly decreased with the increase laser power from 70 to 140 W (corresponding to the laser energy density from 116.7 to 233.3 J/mm3), while exhibiting a slight increase in the laser power range of 140–280 W (the laser energy density of 233.3–466.7 J/mm3). Additionally, the SLM316LSS specimen at a laser power of 140 W reached the hardness of ∼252 HV, the yield strength of ∼605 MPa and the ultimate tensile strength of ∼710 MPa, along with the elongation to fracture of ∼32.5%, respectively, due to the lowest defect concentration and the presence of twin boundaries and textures, combined with SiO2 nano-oxide particles and deformation twinning. However, the crack appeared in the SLM316LSS within the laser power range from 210 to 280 W (the laser energy density from 350.0 to 466.7 J/mm3), and the mean crystallite size was more than 50 μm, which insignificantly affected the mechanical properties of the steel compared with a laser power of 140 W.

A novel green synthesis of CuFe2O4 Nanoparticles from Cissus rotundifolia for photocatalytic and antimicrobial activity evaluation

This paper reports a novel green fabrication of copper ferrite (CuFe2O4) nanoparticles (NPs) from Cissus rotundifolia plant extract. The NPs were characterized by different spectroscopic techniques.The Fourier transform infrared (FT-IR) spectrum exhibited intrinsic stretching at the tetrahedral position of Fe–O at 591 cm−1 and the octahedral stretching of Cu–O at 402 cm−1 respectively. The fine diffraction pattern in the X-Ray diffraction analysis (XRD) showed the formation of well-crystalline NPs. The mean crystallite size of the NPs was calculated to be 17.33 nm. The High-resolution Transmission Electron Microscopic (TEM) analysis showed roughly spherical shape and irregular morphology of the NPs. The Zeta potential was calculated to be −29.7±0.3 mV, indicating a negative charge over the CuFe2O4 NPs. The formation of spinel ferrite was confirmed from the characterization data. The photocatalytic activity of the CuFe2O4 NPs was examined against the methylene blue (MB) dye, showing 82% degradation under UV–Visible light. The reusability experiment showed that the catalytic activity was not much decreased even till the 4th cycle. The antibacterial activity of the synthesized CuFe2O4 NPs was tested against Bacillus subtilis, Staphylococcus aureus, Bacilus pumilis, Escherichia coli, Pseudomonas aeruginosa, and Salmonella abony through the Agar well diffusion method. A zone of inhibition of 12±0.2, and 11±0.4 mm was obtained against Bacillus subtilis and Bacillus pumilis, whereas against E. coli, P. aeruginosa and S. abony it was found to be 14±0.4, 18±0.3, and 12±0.2 mm respectively at 75 mg/mL dose, showing appreciable antibacterial activity.

Preparation of chromium barium oxide catalysts for hydrogen evolution from sodium borohydride methanolysis

This paper describes the synthesis of Cr2O3, Cr1.7Ba0.3O3, and Cr1.4Ba0.6O3 nanoparticles as catalysts to enhance hydrogen evolution in sodium borohydride methanolysis. Various characterization techniques, comprising X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and others were utilized to characterize the prepared nanoparticles. The XRD analysis showed that the formed Cr2O3 exhibits a hexagonal crystal structure, with an estimated mean crystallite size of 24 nm. SEM micrographs showed nanoparticles with homogeneous distributions, exhibiting spherical or distorted spherical shapes. XPS analysis showed that all synthetic Cr2-xBaxO3 materials consist of Cr, O, and the presence of Ba for doped samples. The energy gap for pure Cr2O3 nanoparticles was determined to be 3.28 eV. Inclusion of Ba into the Cr2O3 nanostructure modified the band gap, resulting in values of 2.8 and 1.5 eV at 15 % and 30 % barium content. The hydrogen production rate from NaBH4 methanolysis for Cr2O3, Cr1.7Ba0.3O3, and Cr1.4Ba0.6O3 catalysts were 5984, 31176 and 11913 mL/g.min, respectively.