modern research physics

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Fe Doped CdS nanopaqrticles have been synthesized by a wet chemical method and TG used as a capping agent. The particle size of the nanoparticles calculated from XRD and optical methods has been found in the range 3-5 nm. The x-ray diffraction measurements showed that the nanoparticles have the structure of hexagonal phase. The broadening of XRD patterns indicate that the prepared CdS:Fe samples are nanostructures. The UV absorption results indicated that the doping increased optical band gap of nanoparticles which means the particle size decreased due to Fe doping. Also, effects of doping and capping agent concentration on the luminescence spectra of CdS:Fe nanoparticles investigated

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In this study, Fe₃O₄/SiO₂ core-shell magnetic nanoparticles (NPs) by two-step process were synthesized. First, Fe₃O₄ NPs by co-precipitation method of iron ions (Fe³⁺ and Fe²⁺) in an alkaline medium without using surfactant were synthesized and then silica shell with a non-thermal method without the use of linkers were installed on Fe₃O₄ NPs. facility of this method is noticeable. Results of X-ray powder diffraction patterns show that the inverse spinel structure of Fe3O4 and amorphous silicon was made. Fourier transform infrared spectroscopy confirmed the formation of these structures. There is no additional peak in XRD pattern which indicates that the prepared particles have pure Fe₃O₄ phase. TEM images show that core-shell structure is formed and mean size of NPs is 20 nm. VSM analysis showed that saturation magnetization of Fe3O4 nanoparticles after coating with silicon decreased.