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Nanoparticles of zinc selenide (ZnSe) were produced by an innovative, uncomplicated, and extremely rapid process that took no longer than a few seconds. For the production of zinc ions, zinc chloride was utilized, and selenium was used for the production of selenium ions. The effect of Zn to Se ions ratio on optical properties has been examined. The prepared nanoparticles were tested and characterized by using transmission electron microscope TEM, scanning electron microscope SEM and UV–Visible spectroscopy. The morphological results revealed that the ZnSe has a spherical shape with mean diameter around 15 nm and the band gap of the ZnSe increases with increasing the Zn content in the sample. The prepared materials were tested as antibacterial agent. [ABSTRACT FROM AUTHOR]

In this study, the co-precipitation approach was used to make nanostructured nickel oxide (NiO) commencing with sodium hydroxide (NaOH) and nickel (II) chloride hexahydrate (NiCl2 ⋅ 6H2O). Through the use of X-ray diffraction (XRD), scanning electron microscopes (SEM), UV-visible (UV–Vis) absorption, and Fourier transform infrared (FTIR) imaging, structural and optical studies were investigated. FTIR, photoluminescence (PL), cyclic voltammetry (CV) studies are taken. The synthesized nanoparticles were annealed at 3 0 0 ∘ C and 4 0 0 ∘ C. The face-centered cubic (FCC) structure of the NiO and highly crystallized nanoparticles were revealed by XRD investigations. Observation of FTIR spectra validated the composition of functional groups. Scanning electron microscopy image shows the average size is 24 nm. NiO optical band gap at 3 0 0 ∘ C (3.37 eV) and 4 0 0 ∘ C (2.7 eV) is revealed from UV studies. From CV graph, the sample annealing at 3 0 0 ∘ C and 4 0 0 ∘ C the specific capacitance was 543.6 and 519.8 F/g, respectively. This study signifies the supercapacitor application of nanosized metal oxide. [ABSTRACT FROM AUTHOR]

In this work, the azo dye Congo red (CR) was degraded by a Fe–In2O3 catalyst under the irradiation of ultrasonic. The Fe–In2O3 catalyst was prepared by a fast and moderate solvothermal method followed by the characterization of X-ray diffraction and scanning electron microscope. The effects of operating parameters, such as catalyst composition, catalyst dosage, initial dye concentration, ultrasonic power and ultrasonic frequency on degradation process were discussed. In the experiment, the optimum CR removal of 97.75% in 60 min was achieved under the conditions, i.e., catalyst dosage of 0.06 g ⋅ L − 1 , CR concentration of 10 mg ⋅ L − 1 , ultrasonic frequency of 45 kHz and ultrasonic power of 100 W. Besides, the CR degradation behavior by the catalyst with ultrasonic is well in accordance with the first-order kinetic model. A spherical Fe–In2O3 nanocatalyst with good crystalline structure was successfully synthesized, and the excellent catalytic degradation efficiency for the azo dye congo red under ultrasonic irradiation was shown. The congo red degradation process was fostered by Fe–In2O3 catalyst compared with that of the blank and pure In2O3, which is well in accordance with the first order kinetic model. [ABSTRACT FROM AUTHOR]

Fe3O4 nanoparticles have been widely used as drug carriers, but their toxicity is rarely reported. Herein, we compared the toxicity of novel Fe3O4 nanorings, nanotubes and conventional Fe3O4 nanospheres. The structure, morphology and magnetic properties of Fe3O4 nanoparticles were characterized via X-ray diffraction, scanning electron microscope and vibrating sample magnetometer. Scanning electron microscope images revealed that the morphologies of Fe3O4 particles were annular, tubular or spherical. The magnetic property measurements demonstrated that saturation magnetization values of nanorings, nanotubes and nanospheres were 85.3, 90.1 and 74.8 emu/g, respectively. In addition, the cytotoxic effects on the 264.7 mouse macrophages cells of Fe3O4 nanorings, nanotubes and nanospheres were determined by cck-8 test and TUNEL staining assay. Cell viability was slightly decreased on spherical Fe3O4 nanoparticles compared to annular and tubular Fe3O4 nanoparticles. Fe3O4 nanospheres are synthesized by one-step synthesis method. Nanorings and nanotubes are first synthesized into Fe3O4 nanoparticles by hydrothermal method and then reduced to Fe3O4 nanoparticles. The synthesis method of nanotubes is basically the same as that of nanorings, the only difference is the amount of NH4H2PO4 added. Hollow nanostructured materials (compare with nanospheres) can reduce particle sedimentation agglomeration and toxicity. [ABSTRACT FROM AUTHOR]

In this work, the crystal and surface structures of Y2O3 nanoparticles were explored. The exploration of crystal structure was carried out by X-ray diffraction method at room temperature and under normal conditions. It was found that the crystal structure of the Y2O3 compound has a cubic symmetry with an Ia-3 space group. The lattice parameters have the values: a = b = c = 1 0. 5 9 5 8 Å. The surface structure was studied at room temperature and under normal conditions on Scanning Electron Microscope (SEM) microscope. It was found that the nanoparticles of the Y2O3 compound being in the range 20–40 nm are of d ≈ 3 0 nm size. [ABSTRACT FROM AUTHOR]

In this study, positively charged polystyrene-co-poly (ar-vinylbenzyl) trimethylammonium nanoparticles loading with Aggregation Induced Emission (AIE) fluorescent molecule sulfonated 9,10-distyrylanthracene derivatives (SDSA) by coulomb force denoted as SDSA/PS-co-PVBTAC have been prepared. The size, size distribution and morphology of nanoparticles have been tested by Dynamic light scattering (DLS) and Scanning electron microscope (SEM). The synthesized nanoparticles possess uniform size, good monodispersity and low biological toxicity. The AIE-type SDSA/PS-co-PVBTAC showed good fluorescence stability at pH from 3 to 10. It has been proved that the biological macromolecules including Bovine Serum Albumin (BSA), DNA and RNA can amplify the cell imaging signals. Moreover, the AIE-type nanoparticles have been shown to perform fluorescent imaging of various cells. It suggests that the prepared SDSA/PS-co-PVBTAC can be used as a new biological probe in the field of cell imaging and detection, as well as expanding the application of AIE fluorescent molecules in biosensing field. Through Coulomb force of nanoparticles with AIE fluorophore SDSA, hybrid polymeric nanoparticles SDSA/PS-co-PVBTAC for various cells imaging were prepared. It has been proven that the biological macromolecules can amplify the fluorescence signals, accompanied with good fluorescence stability at pH from 3 to 10. The electrostatic attraction between the positively charged nanoparticles and the negatively charged cell membrane is conducive to improve the cellular uptake of nanoparticle, as well as the effect of intracellular imaging. [ABSTRACT FROM AUTHOR]

In this study, we report, for the first time, on synthesis of lanthanum oxide La 2 O 3 nanoparticles NPs by laser ablation in water without using surfactant. The effect of laser wavelength on the optical and structural properties of La 2 O 3 NPs was investigated. X-ray diffraction studies show formation of polycrystalline lanthanum oxide with pure cubic phase and the crystallinity of the nanoparticles synthesized with λ = 5 3 2  nm was better than that prepared with λ = 1 0 6 4  nm. The optical absorption investigations reveal that a strong absorption peak at 234 nm was observed for La 2 O 3 NPs prepared at 532 nm laser wavelength. The optical energy gap of La 2 O 3 NPs synthesized with 532 and 1064 nm laser wavelengths were 5 and 4.5 eV, respectively. Scanning electron microscope (SEM) investigation indicated the formation of nanoparticles with average particle size of 35 nm for La 2 O 3 prepared with 532 nm and was 75 nm for La 2 O 3 prepared with 1064 nm laser wavelength. The effect of laser wavelength on the optoelectronic properties of hybrid In/p- La 2 O 3 /n-Si photodetector was studied. The responsivity studies of the photodetectors show the presence of two response peaks at 250 and 750 nm. [ABSTRACT FROM AUTHOR]

Nanocrystalline SnO2 powder has been successfully synthesized by using tin(II) chloride dihydrate (SnCl 2 ⋅ 2 H2O), distilled water and liquid ammonia by the simple chemical co-precipitation method at room temperature using different SnCl 2 ⋅ 2 H2O molar concentration of 0.3 M, 0.4 M and 0.5 M. The structural properties of the prepared SnO2 and transition metal doped SnO2 nanoparticles has been studied using X-ray diffraction method and scanning electron microscope. The composition of the powders has been analyzed using energy dispersive X-ray analysis. The XRD pattern of the SnO2 nanoparticles indicates the formation of single-phase rutile tetragonal structure. The grain size is found to be in the range of 3–7 nm and is found to increase with increasing SnCl2 molar concentration. The absorption spectra revealed that the bandgap decreased from 3.74 eV to 3.59 eV with increasing SnCl2 molar concentration. The photoluminescence spectra of SnO2 nanoparticles showed a visible broad luminescence band in the region of 385–430 nm. The magnetic studies have been carried out using the hysteresis loop obtained from a vibrating sample magnetometer. The SnO2 samples using 0.3 and 0.4 SnCl2 molar concentration exhibited ferromagnetic behavior whereas the SnO2 sample prepared using 0.5 M SnCl 2 ⋅ 2 H2O exhibited paramagnetic nature. [ABSTRACT FROM AUTHOR]

Potassium chloride (KCl) nanoparticles were synthesized by ball milling technique with different milling time. The effect of milling time on structural and optical properties was investigated. The structural properties of the purchased samples are characterized by Raman spectroscopy, scanning electron microscope and X-ray diffraction techniques. The Raman spectroscopy of the KCl hints at an excellent alloying behavior of those compounds and a preferred crystal structure for certain composition. The optical band is calculated by analyzing the spectral behavior of the absorption coefficient in the absorption region which revealed direct transitions. The value optical band increases (4.02–5.11 eV) with increasing milling time (0–15 h) due to quantum confinement after the ball milling process. The refractive and absorption indices were calculated for all samples. The model of Wemple–DiDomenico was used to calculate the dispersion parameters. The nonlinear susceptibility of the third order and the nonlinear refractive index were calculated by linear optical parameters using the generalized Miller rule. Mechanical milling for different milling times (0, 5, 10 and 15 h) by a planetary ball mill with zirconium oxide balls has been carried out for milling KCl. The images of as-purchased KCl have regular uniformly grains distributed like cubic particles with size of around 10 μm. By increasing the milling time to 15 h, these individual regular shapes form a smaller reasonably dense having a size less than 500 nm. [ABSTRACT FROM AUTHOR]

Fe3O4 nanoparticles coating with poly dimethyl diallyl ammonium chloride (Fe3O4/PDDA) as novel magnetic adsorbents were synthesized with chemical co-precipitation method to study the removal capacity of organic phosphonates from aqueous solution. The as-prepared magnetic absorbents were characterized for the morphology, material structure and surface properties by SEM, TEM, FT-IR, XRD, TGA and BET. HEDP was employed as a common organic phosphonate to investigate the adsorption performance. Substantial quaternary ammonium groups existing on the surface of Fe3O4/PDDA could enhance the absorption of HEDP with electrostatic attraction. In the optimum condition (4 mg adsorbent dosage, 11.0 pH, 36 mg/L HEDP solution and 120 min adsorption time), the maximum adsorption capacity ( q m ) for HEDP could reach 254.86 mg/g. The kinetic study revealed that the adsorption process followed the pseudo-second-order model. The adsorption isotherm fitted closely to the Freundlich model. The as-prepared magnetic adsorbents exhibited notable reusability in some cycles and were easily separated from the solution with the external magnetic field. These as-prepared Fe3O4/PDDA nanoparticles have the potential as an environmental-friendly adsorbent for organic phosphonates removal from waste-water. Fe3O4 nanoparticles modified with PDDA have been successfully fabricated by the chemical co-precipitation method. The PDDA on the surface of particles provided substantial quaternary ammonium groups which enhanced the absorption of HEDP from aqueous solutions with electrostatic attraction. These magnetic nanoparticles exhibited good reusability in several cycles. [ABSTRACT FROM AUTHOR]

The flower-like Cu2O nanostructures were hydrothermally synthesized without using any template or surfactant. The influences of hydrothermal temperature, reaction time and reactants concentrations on the growth of nanostructures were investigated in detail. The samples were characterized by scanning electron microscope (SEM) and X-ray powder diffraction (XRD). Cu2O crystals with different shapes, i.e., flower-like (F-product) cubic box (CB-product) and cubic box with holes in each face (CBH-product), were synthesized by controlling the synthesis parameters and explored for CO catalytic oxidation. It was found that F-product showed higher catalytic than others. [ABSTRACT FROM AUTHOR]

Nanoparticle Lead sulfide was synthesized via simple chemical method and deposited on glass substrates at different substrate temperatures by thermal evaporation technique. The synthesized nanoparticle was analyzed and confirmed by X-ray diffraction (XRD), Scanning electron microscopy SEM with EDX and thermogravimetry. The structural, optical, morphological and electrical properties of the deposited films were studied using XRD, UV-Vis, Raman, SEM with EDX, atomicforce microscopy AFM and Hall Effect measurements. The thickness of the deposited samples was measured using thickness profilometer. The Raman shift in the peak occurs toward lower energy with increasing substrate temperature deposited lead sulfide. The Z-scan study with open aperture was carried out at 532 nm using 5 ns laser pulse on the deposited films which shows that nonlinear absorption arises from saturable absorption process. The deposited film exhibits p-type conductivity in Hall measurement. [ABSTRACT FROM AUTHOR]

In this paper, we firstly synthesized glycyrrhetinic acid-modified double amino-terminated poloxamer 188 (GA--NH--POLO--NH--GA). The structure of the synthesized compound was confirmed by 'H-NMR and Fourier transform infrared (FT-IR) spectroscopy. Then the nano-particles composed of GA-NH-POLO-NH-GA/chitosan (GA-NH-POLO-NH-GA/CTS) were prepared by an ionic gelation process. The characterization of the nanoparticles was measured by dynamic light scattering (DLS) and scanning electron microscope (SEM). The results showed that the nanoparticles were well dispersed with a spherical shape and the particle size was distributed between 100 nm and 300 nm. The cytotoxicity based on MTT assay against cells (QGY-7703 cells and L929 cells) showed that the nanoparticles had low toxicity and good biocompatibility. The encapsulation efficiency and drug loading of 5-fluorouracil-loaded nano-particles (5-FU nanoparticles) were measured by high-performance liquid chromatography (HPLC) and fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorbance. The encapsula-tion of 5-Fu-loaded CTS nanoparticles was 12.8% and the drug loading was 2.9%, while the encapsulation of 5-Fu-loaded GA-NH-POLO-NH-GA/CTS nanoparticles was 20.9% and the drug loading was 3.36%. The release profile showed that the GA-NH-POLO-NH-GA/CTS nanoparticles were available for sustained release of 5-Fu. The GA--NH--POLO--NH--GA/CTS nanoparticles have a higher affinity to the QGY-7703 cells, so indicated that the GA-NH-POLO-NH-GA/CTS nanoparticles have the capacity of liver-targeting in vitro. [ABSTRACT FROM AUTHOR]

Composites of polyvinyl alcohol (PVA) containing silver nanoparticles were prepared using in situ synthesis of nanoparticles. Structure and properties of these composites were investigated using UV-Vis spectroscopy, XRD, DSC, SEM and AFM. The studies show that PVA can reduce the 3 to yield silver nanoparticles and in the process forms bonds with PVA chains. The anti-bacterial properties of these films were studied by qualitative as well as quantitative methods which gave the values of 98% for gram positive and 89% for gram negative bacteria. [ABSTRACT FROM AUTHOR]

Nano nalidixic acid was prepared by ultrasonic method in carbon tetrachloride. Nano nalidixic acid (quinolone antibiotic) was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscope (SEM). The antibacte-rial activities of nano nalidixic acid were tested against microorganisms and compared with the microscale drug. The results show that nano nalidixic acid has good inhibitory properties against two Gram-positive species, Staphylococcus aureus and Bacillus sub-tilis. Nano nalidixic acid also showed good antifungal activity against Candida albicans. Nano nalidixic acid can be injected into the human body as a decontaminating agent to prevent the growth of harmful microorganisms more effectively than the micro-sized drug. [ABSTRACT FROM AUTHOR]

In this work, nanoparticles were deposited on quartz glass substrates by magnetron sputtering method, and the morphology was characterized by SEM. nanoparticle surface plasmon resonance characteristics were observed by transmittance measurement. The experimental results demonstrated an increase in particle size that was correlated to an increase in sputtering time and a plasmon resonance absorption peak redshift. This phenomenon was partially explained by Mie scattering model. The differences between our theoretical analysis and experimental results show that both the shape of and the spacing between nanoparticles are key parameters affecting plasmon resonance peak location. [ABSTRACT FROM AUTHOR]

A model for explaining deviations of positions in self-organized nanoparticles on a substrate from their corresponding positions in perfect organization is proposed. The model predictions were compared with SEM/TEM images and reported by some authors. We found a consistence between the model predictions with the data of , and nanoparticles organization on various substrates. Theoretical explanation of self-organized nanoparticles was developed using both nonlinear oscillation model of hexagonal lattice and Hamaker equation to obtain respectively the vibration energy and its spring constant. We inspected the model for comparison to the several observations to some SEM or TEM images available from some authors such as Ag, Fe3O4 and SiO2 nanoparticles. Interestingly there is an agreement between the present model and the observation results. The model showed briefly the dependence of the deviation to the Hamaker constant, average diameter of the nanoparticles and the average distance among them. Furthermore, using this model, the deviation of the self-organized nanoparticles can be minimized. [ABSTRACT FROM AUTHOR]

α-Fe2O3 nanoparticles were obtained by a mechanical alloying of micrometer-sized powder at different milling times. Samples were characterized by X-ray powder diffraction, scanning electron microscope (SEM), Mössbauer spectrometry, and vibrating sample magnetometer (VSM). A qualitative and quantitative phase analyses using the Rietveld method have been performed based on the XRD data. The results did not reveal any phase change during the milling. The average particle size decreases with a prolongation of milling times, while the lattice parameters, unit cell volume, and microstrain increase. Mössbauer measurement shows that there are two components, one nanometric and other micrometric. The magnetic hysteresis loops shows that the samples are typical of ferromagnet with superparamagnetic fraction in the material. [ABSTRACT FROM AUTHOR]

Ag nanoparticle deposition on the surface of spherical SiO2 nanoparticles was studied to achieve hybrid structure of Ag–SiO2 nanocomposite. SiO2 nanoparticles were served as seeds for continuous Ag metal deposition. The ratio of elements and morphology was studied with scanning electron microscope energy dispersive X-ray and transmission electron microscope. The antibacterial properties of Ag–SiO2 nanocomposite were examined. The homogeneously formed Ag nanoparticles on the surface of SiO2 nanoparticles without aggregation of Ag nanoparticles showed excellent antibacterial abilities. [ABSTRACT FROM AUTHOR]

This study briefly reports a newly developed nanopatterning technology utilizing a so-called micro droplet jetting system, which can be used in various applications such as nanofabrication. Compared with the conventional methods, this technology has the advantages as follows: it can be manipulated easily and patterned freely as the user requires; furthermore, it shows high-reliability and high-stability with very low cost. The typical specs of the micro droplet jetting system for fabricating nanodevice show as follows: (1) nanoparticle size: 50–60 nm; (2) characteristic wavelength: 400–450 nm; (3) volume of droplet: 6 ppl; (4) size of pixel: 70 μm. In this article, the nanopatterning technology adopting the micro droplet jetting system has been demonstrated to be useful for nanopatterning the pixels which consist of nanoparticles, organic luminescent materials. In addition, the micro topography and the luminescent property of the patterned surface have been characterized by using Scanning Electron Microscope (SEM) and fluorescence microscope, respectively. Finally, the fluorescence of the patterned nanoparticles was observed. [ABSTRACT FROM AUTHOR]

Poly(St-co-BuA)/silica nanocomposite latexes were synthesized via conventional emulsion polymerization in the presence of 3-(trimethoxysilyl)propyl methacrylate modified colloidal nano-silica. The effects of surface property, particle size and content of colloidal nano-silica as well as the concentrations of monomer and surfactant on the morphology of nanocomposite latex particles were investigated by transmission electron microscope (TEM) and scanning electron microscope (SEM) in detail. Various interesting morphologies such as grape-like, Chinese gooseberry-like, pomegranate-like and normal core-shell structures were observed. Droplet nucleation mechanism competing with micelle nucleation mechanism was proposed to explain the morphological evolution of the nanocomposite particle. [ABSTRACT FROM AUTHOR]

Micropatterned films are attractive materials with potentials applicable in the fields of photonics, electronics, biotechnology, and so on. Fabrication of honeycomb-patterned microporous films ("honeycomb films") by casting dilute solution of various types of polymers under high humidity has been already reported. Introduction of luminescent nanoparticles into micropores of the film is investigated to realize photofunctional materials. Novel luminescent monodisperse nanoparticles containing europium or terbium complexes have been prepared for this experiment. By a scanning electron microscope (SEM), many wrinkles were observed on the surface of lanthanide-containing nanoparticles. Zeta potential of the lanthanide-containing nanoparticles was positive. Composites of honeycomb film and the nanoparticles, the latter embedded in the micropores, were fabricated by dropping water dispersion of mixture of the europium-, terbium-, and no-dye-containing nanoparticles on the films. The number of the nanoparticles in a micropore was estimated no less than 400 by analyzing SEM images. The ratio of emission intensity of terbium to that of europium in the individual micropores of the composites fluctuated and deviated from the intensity ratio in bulk. Numerical simulation confirmed this tendency qualitatively. [ABSTRACT FROM AUTHOR]

Synthesis of uniform nanocrystalline anatase TiO2 by sol–gel method was investigated using different thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. Thermal treatment of the precursor at 350°C for 2 h in air results in the formation of nanocrystalline anatase TiO2 with the average crystal size of 21.5 nm. Quantitative analysis through energy dispersive X-ray spectroscopy (EDS) indicated that the atomic ratio of Ti:O ≈ 1:1 is close to the stoichiometric ratio of TiO2, leading to the evident fact that the prepared nanoparticles are indeed the TiO2 material. [ABSTRACT FROM AUTHOR]

Polycrystalline silicon carbide (P-SiC) films containing SiC nanoparticles and Er were prepared by r.f. reactive magnetron co-sputtering technique with SiC and Er targets on low-temperature silicon (111) and silicon dioxide substrates with the mixed gas of pure argon, methane, and hydrogen. Surface morphology and photoluminescence (PL) properties of them were measured by field-emission scanning electron microscope and Raman spectroscopy. The peak position, intensity, and the full width at half maximum (FWHM) of PL spectra were relevant with Er doping levels and deposition conditions. [ABSTRACT FROM AUTHOR]

The cadmium-doped SnO2 nanoparticles have been successfully prepared by a simple mechanochemical reaction and subsequent thermal treatment. The samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Thermal treatment of the as-milled powder at 700°C for 2 h resulted in the formation of Cd-SnO2 nanoparticles with an average crystal size of 13 nm, varying with the calcination temperature. The effect of doped cadmium on the crystal size of the nanoparticles was investigated. The lattice parameter (c) of the Cd-SnO2 nanoparticles, lower than that of pure SnO2, decreased with increasing amount of doped cadmium. The apparent activation energy of Cd-SnO2 nanocrystal growth during calcination of the precursor was calculated to be 70.8 kJ/mol. The mechanochemical method is a novel, cheap and convenient technique especially suitable for large-scale synthesis of nanosized materials. [ABSTRACT FROM AUTHOR]