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In this work, the gas sensing properties of ZnS/Porous silicon heterostructures have been investigated. . Zinc sulfide(ZnS) with high gas sensing performance is successfully synthesized over the Porous silicon substrate by the spray pyrolysis method. The properties of the as-prepared samples were characterized X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform spectrum (FTIR) and optical properties. The results reveal that the properties of the ZnS/Porous silicon heterostructures enhanced when the when the ZnS concentration is increased. The performance ZnS/Porous silicon as a gas-sensing show that the maximum sensitivity is found to be 5.11 at ZnS concentration of 0.5 M and etching time of 15 min compared to the other sensitivities. The ZnS-PSi heterojunction based gas sensor may be used for UV-light photo-detectors due to a valuable properties such as high sensitivity and fast response. [ABSTRACT FROM AUTHOR]

Nanocrystalline particles of lead sulphide and cobalt doped lead sulphide were prepared by a hydrothermal method. The crystalline nature and particle size of the samples were characterized by powder X-ray diffraction analysis (XRD). The thermal stability of nanocrystals was studied by thermo gravimetric analysis (TGA). The morphology of prepared nanocrystals was studied by scanning electron microscope (SEM) and the presence of Co2+ in the sample was confirmed by energy dispersive X-ray analysis (EDX). The formation of the lead sulphide and cobalt doped lead sulphide nanoparticles was analyzed using FTIR analysis. The optical absorption of the synthesized samples was studied using UV absorption spectral analysis. The photoluminescence properties were studied using PL spectral analysis. The degradation of methyl blue (MB) in aqueous medium was studied by using lead sulphide nanoparticles. The cobalt doped lead sulphide works as an efficient photocatalyst for degradation of methyl blue dye. [ABSTRACT FROM AUTHOR]

In the present work, conventional chemical co-precipitation method was employed for the prepation of Nickel (2,4,6,8&10 at % of Ni) doped CdS nanoparticles. The particle size and lattice parameters for each sample are determined from X-ray diffraction (XRD) analysis. From XRD patterns the broadening of the diffraction peaks indicates the nanostructure nature of the samples. Surface morphology of the samples was studied by Scanning Electron Microscope (SEM). Compositional Elemental analysis of data is obtained from Energy Dispersive Analysis of X-ray (EDAX) plots. [ABSTRACT FROM AUTHOR]

Semiconductor ZnS nanoparticles have been successfully synthesized from solutions containing a nonionic surfactant, Triton X-100 (t-octyl-(OCH2CH2)x OH, x = 9,10). The particle size was estimated as 7.7 nm. The optical spectra enabled to conclude that these nanoparticles exhibit quantum size effects. The prepared nanoparticles have been characterized by x-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) and the results are discussed in this paper in detail. [ABSTRACT FROM AUTHOR]

Nanocrystalline Se0.8Te0.2 films were grown on quartz substrates by using thermal evaporation technique. Structural and optical properties of as-grown and annealed samples were investigated with XRD, SEM and UV-visible spectroscopy. The x-ray diffraction pattern at room temperature shows that the sample are formed in single phase with monoclinic crystal symmetry having space group Cm. Surface morphology of the glass as-grown film was investigated via scanning electron microscopy (SEM). The typical diameter of as-grown nanocrystalline sample is found to be 50 nm, which is consistent with crystallite size calculated by XRD data using Scherrer equation. The UV-visible absorption spectra of the nanocrystals show that the optical band gap of as-grown and annealed samples are situated systematically in the range of 2.10 - 1.95 eV, which is quite larger than the bulk phase of the materials. The results have been explained on the basis of the close interplay between the structural and optical properties. [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]