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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]

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]

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]

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]

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]

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]

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]

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]

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]