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Herein, we report that synthesis of ZnS/Bi2S3 and Bi2S3/ZnS core-shell nanostructure prepared by 'one-pot' chemical method. We have studied the effect of structural, morphological, optical and thermal properties by exchanging the inner and outer layer of core-shell nanoparticles. The samples were studied using various characterization techniques such as XRD, TEM, FTIR, UV-Vis, Photoluminescence and TG-DTA. The XRD and TEM results demonstrated that the synthesized core-shell nanoparticles were in cubic (ZnS)-orthorhombic (Bi2S3) mixed crystal structures with a diameter of 18.6 nm and 16.3 nm with extremely monodispersing. The obtained result provides a new and simple route for synthesis of sulfide-based core-shell nanoparticles with high crystal quality. [ABSTRACT FROM AUTHOR]

High quality silver (Ag) decorated CeO2 nanoparticles were prepared by a facile one-step chemical method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), High resolution transmission electron microscopy (HR-TEM), fourier transform infrared spectrometer (FT-IR), electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), UV–Visible absorption (UV–Vis), photoluminescence (PL) and thermogravimetric analysis. The decoration of Ag on CeO2 surface was confirmed by XRD, EPR and HR-TEM analysis. Harmful textile pollutant Rose Bengal dye was degraded under sunlight using the novel Ag decorated CeO2 catalyst. It was found that great enhancement of the degradation efficiency for Ag/CeO2 compared to pure CeO2, it can be ascribed mainly due to decrease in its band gap and charge carrier recombination rate. The Ag/CeO2 sample exhibited an efficient photocatalytic characteristic for degrading RB under visible light irradiation with a high degradation rate of 96% after 3 h. With the help of various characterizations, a possible degradation mechanism has been proposed which shows the effect of generation of oxygen vacancies owing to the decoration of Ag on the CeO2 surface. [ABSTRACT FROM AUTHOR]

Core‐shell CdS/ZnS (Zn 0.025‒0.125 M) and CdS:Cu2+(1%)/ZnS nanoparticles were successfully synthesized using a chemical method. X‐ray diffraction (XRD), high‐resolution transmission electron microscopy (HR TEM), photoluminescence (PL) and UV/Visible (UV/Vis) techniques were used to characterize the novel CdS/ZnS and CdS:Cu2+/ZnS core–shell nanoparticles. All absorption peaks of the synthesized samples were highly blue‐shifted from the bulk CdS and ZnS. Very narrow and symmetric PL emission was observed in the yellow region for core–shell CdS/ZnS. Furthermore, the PL emission of CdS/ZnS was tuned into orange region by incorporate the Cu ion into the core CdS lattice. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Monodispersed ZnS nanoparticles have been successfully synthesized by a chemical precipitation method in an air atmosphere using polyvinylpyrrolidone (PVP) and sodium hexametaphosphate (SHMP) as surfactants. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectrometer (FT-IR), UV-Vis optical absorption and photoluminescence (PL) spectra. Prepared surfactants capped ZnS nanoparticles are highly homogeneous and well dispersed. Optical absorption spectra showed a strong blue shift from the uncapped particles due to the quantum confinement effect. The capped ZnS emission intensity is enhanced than more the uncapped particles. The size of the synthesized particles is around 4-6.5 nm range. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Excellent luminescence properties of ZnS/CdS/ZnO and ZnO/ZnS/CdS nanocrystallites synthesized through a simple chemical method at room temperature are reported. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), UV–visible absorption and photoluminescence techniques were used to characterize the undoped ZnS, CdS and ZnO and the novel ZnS/CdS/ZnO and ZnO/ZnS/CdS nanoparticles. The optical properties of ZnS/CdS/ZnO and ZnO/ZnS/CdS nanoparticles reflect a combinational effect of the photoluminescent properties of ZnS, CdS and ZnO. [Copyright &y& Elsevier]

Abstract: ZnO, ZnS and ZnO/ZnS nanocomposites were successfully synthesized by chemical method in an air atmosphere. Water–ethanol matrix was used as solvent. The as-obtained samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–visible (UV–vis) and photoluminescence (PL) spectrophotometer. The results showed that the ZnS nanoparticles are cubic in structure with the size of about 5nm growed on the surface of the hexagonal ZnO nanocomposites. The optical study of ZnO/ZnS nanocomposites showed an enhanced PL emission in visible region. The photoluminescence property of the ZnO/ZnS core/shell nanocomposites is varied with respect to the shell thicknesses. PL quenching is observed by increasing of shell thickness on ZnO. [Copyright &y& Elsevier]

Abstract: Water soluble ZnS, CdS and multilayer coated ZnS/CdS/ZnS nanocomposites were successfully synthesized by chemical method in an air atmosphere. Structural, morphology and optical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–visible absorption (UV–vis) and photoluminescence (PL) spectrometer. The obtained particles are highly crystalline and monodisperse with an average particle size of 4.3–5.6nm range. A significant red shift was observed by increasing the CdS thickness in ZnS/CdS/ZnS nanocomposites. The PL position of ZnS and CdS compound is tuned in the visible region by the way of alteration layer thickness. [Copyright &y& Elsevier]

Abstract: Mn2+­doped ZnS nanoparticles have been prepared through the reverse micelles method using sodium bis (2–ethylhexyl) sulfosuccinate (AOT) as a surfactant. The prepared particles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infra-red spectrometer (FT-IR), UV–vis spectrometry, photoluminescence (PL), electron spin resonance (ESR) and thermogravimetry–differential scanning calorimetry (TG–DSC). [Copyright &y& Elsevier]

Abstract: Photoluminescence properties of trioctylphosphine oxide (TOPO) capped ZnS:Mn2+ nanoparticles were investigated. The particles were synthesized using chemical precipitation method at 160°C. The nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), particles size analyzer (PSA), Fourier transform infra-red spectrometer (FT-IR), ultraviolet–visible (UV–Vis) and photoluminescence (PL). The PL results showed that the yellow-orange emission peak centered at 580nm. XRD and TEM analysis results reveal the formation of cubic structure ZnS:Mn2+ particles with an average size of 3.5nm. The TOPO capped ZnS:Mn2+ nanoparticles showed enhanced luminescence property compared with that of the uncapped particles. [Copyright &y& Elsevier]

Abstract: Zinc sulfide semiconductor nanocrystals doped Mn2+ have been synthesized via a solution-based method utilizing optimum dopant concentration (4%) and employing polyvinyl pyrrolidone (PVP) and sodium hexametapolyphosphate (SHMP) as capping agents. UV–vis absorbance spectra for all of the synthesized nanocrystals show an exitonic peak at around 310nm. The particle size and morphology were characterized by scanning electron microscopy (SEM), FT-IR, X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence spectrum (PL). Diffraction data confirmed that the crystallite size is around 3–5nm. Room temperature photoluminescence (PL) spectrum for the bare ZnS sample shows a strong band at ∼445nm. The uncapped and capped(SHMP, PVP) ZnS:Mn2+ samples show a strong and broad band in the ∼580–585nm range. [ABSTRACT FROM AUTHOR]

Photoluminescence properties of polyvinyl alcohol (PVA) capped ZnS:Mn2+ nanoparticles are reported. The particles were synthesized using chemical precipitation method. The nanoparticles are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible (UV/Vis) and photoluminescence (PL). XRD and TEM studies show the formation of cubic PVA-ZnS:Mn2+ particles with an average size of ∼3 nm. The capped ZnS:Mn2+ nanoparticles showed enhanced luminescence property compared with that of the uncapped ZnS:Mn2+ particles. [ABSTRACT FROM AUTHOR]

The monodisperse of the undoped ZnS and Mn2+-doped ZnS nanoparticles were synthesized through chemical precipitation method using a high-boiling solvent. The prepared nanostructures of the particles have been analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), UV-vis spectrometer and photoluminescence (PL) techniques. The size of the particles is found to be 3-5 nm range. The Mn2+-doped ZnS nanoparticles dispersed in ethylene glycol (EG) shows the PL emission in the visible region 400-650 nm under UV excitation. [ABSTRACT FROM AUTHOR]

Mn2+ - doped ZnS nanoparticles were synthesized by a chemical precipitation method at air atmosphere. The synthesis of water-soluble Mn2+- doped ZnS nanocrystals with EDTA as a stabilizer was described. From the peak broadening of the X-ray diffraction, the particle size is found to be 4.5 nm when EDTA was not used as a stabilizer and size is reduced to 3.6 nm with EDTA. The particle size and properties are studied using SEM and photoluminescence. The emission peak of the sample corresponding to photoluminescence is observed at 591 nm. [ABSTRACT FROM AUTHOR]

Highlights: [•] Multilayer core–shell nanocomposites have been successfully synthesized. [•] Ball like ZnO/CdS/ZnS composites is obtained by stabilized in de-ionized water. [•] Enhanced PL emission is observed for ZnO/CdS/ZnS nanocomposites. [ABSTRACT FROM AUTHOR]

Abstract: ZnS and transition metal (Mn, Co, Ni, Cu, Ag and Cd) doped ZnS were synthesized using chemical precipitation method in an air atmosphere. The structural and optical properties were studied using various techniques. The X-ray diffraction (XRD) analysis show that the particles are in cubic structure. The mean size of the nanoparticles calculated through Scherrer equation is in the range of 4–6.1nm. Elemental dispersive (EDX) analysis of doped samples reveals the presence of doping ions. The scanning electron microscopic (SEM) and transmission electron microscopic (TEM) studies show that the synthesized particles are in spherical shape. Optical characterization of both undoped and doped samples was carried out by ultraviolet–visible (UV–Vis) and photoluminescence (PL) spectroscopy. The absorption spectra of all the samples are blue shifted from the bulk ZnS. An optimum doping level of the transition metals for enhanced PL properties are found through optical study. [Copyright &y& Elsevier]