1.Article (31)

Permanent URI for this collectionhttps://dspace.psgrkcw.com/handle/123456789/4258

Browse

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    EFFECT OF PARTICLE SIZE ON OPTICAL AND ELECTRICAL PROPERTIES IN MIXED CDS AND NIS NANOPARTICLES SYNTHESIS BY ULTRASONIC WAVE IRRADIATION METHOD
    (Elsevier, 2016-12) Mohanraj, V; Jayaprakash, R; Robert, R; Balavijayalakshmi, J; Gopi, S
    The mixed phase CdS and NiS nanoparticles are prepared by adopting ultrasonic wave irradiation method under different doping concentration of Ni in CdS. The well defined nano spheres are obtained during this synthesis process. The predicted particle sizes from X-ray diffraction (XRD) analysis are found to lie in the range between 37 and 49 nm. The effective doping of Ni lead to form the mixture of two phases such as CdS and NiS. The respective change due to the formation of mixture of CdS and NiS is reflected well in the band gap energy which is measured in Diffused Reflectance Spectra (DRS). It is predicted in the range of 2.41–2.23 eV respectively. Consistency of particle size with XRD are confirmed from Transmission Electron Microscope (TEM) images and also identified the presence of Nickel Sulfide and Cadmium Sulfide in nanostate with average particle size as 54 nm. The Energy Dispersive X-ray (EDAX) analysis confirmed the existence of Ni, Cd and S the doping levels. The optical absorption analysis of samples are performed in UV–vis range 400–600 nm. The synthesized samples are further characterized Fourier Transform Infrared (FT-IR) spectroscopy, Thermogravimetric (TGA) analysis, I-V characteristic and conductivity measurements.
  • No Thumbnail Available
    Item
    INVESTIGATION OF STRUCTURAL, OPTICAL AND MORPHOLOGICAL PROPERTIES OF COPPER DOPED ZINC SULPHIDE NANOPARTICLES
    (Elsevier, 2016-06-15) Balavijayalakshmi, J; Manju, S
    Semiconductor nanoparticles doped with transition metal ions can influence the transition probabilities and electronic structure. The undoped and copper doped zinc sulphide nanoparticles with various concentrations are synthesized by wet chemical co-precipitation method. These nanoparticles are characterized by using X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), UV–visible (UV–vis) absorption spectroscopy, Fourier Transform Infrared (FT-IR) Spectroscopy, conductivity measurement and time-resolved photoluminescence studies. X-ray powder diffraction analysis reveals that the synthesized samples have cubic zinc blende structure. The Scanning Electron Microscope shows the synthesized nanoparticles are agglomerated. The UV–visible spectra reveal the absorption edge is red shifted. The FT-IR spectra show vibrational peaks around 617 cm−1 which indicate the presence of Cu–S stretching modes. The AC conductivity measurement confirms the semiconducting nature and shows a marked increase in conductivity as the doping concentration of copper increases. The photoluminescence shows that the emission at 426 nm may be due to transition from the conduction band to the zinc vacancies. These transition metal ions doped semiconductor nanoparticles have important applications in solid state lighting, imaging, and other photonic devices.