Browsing by Author "Manju S"

Now showing 1 - 3 of 3

INVESTIGATION OF STRUCTURAL, OPTICAL AND MORPHOLOGICAL PROPERTIES OF COPPER DOPED ZINC SULPHIDE NANOPARTICLES
(Pergamon / Materials Science in Semiconductor Processing, 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 photo luminescence 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 617cm-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.
SYNTHESIS AND CHARACTERIZATION OF CUPRIC CHLORIDE DOPED ZINC SULPHIDE NANOPARTICLES
(SRM University, Kattankulathur, Chennai, 2015-02-04) Balavijayalakshmi J; Manju S; Lavanya S
In recent years, the research on semiconductor nanoparticles has stimulated much interest because of their unique optical and electrical properties. The nanosized semiconductor crystallites could produce optical properties which are different from bulk materials. Among the semiconductor nanoparticles, Zinc Sulphide is an important II–VI semiconductor material researched extensively because of its wide range of applications in electroluminescence devices, phosphors, light emitting displays and optical sensors. Semiconductor nanoparticles doped with transition metal ions have attracted much attention because of their luminescent properties. Hence an attempt is made to synthesize cupric chloride doped zinc sulphide nanoparticles. The synthesized nanoparticles are subjected to X-ray diffraction to calculate the average nano-crystalline size using Debye – Scherrer formula. The optical properties of the samples are studied using UV-Vis Spectroscopy. The morphological analysis of the sample is studied using Scanning Electron Microscope (SEM). FT-IR spectroscopy is used to determine the chemical bonding in the synthesized sample.
SYNTHESIS AND CHARACTERIZATION OF CUPRIC CHLORIDE DOPED ZINC SULPHIDE NANOPARTICLES
(Sphinx Knowledge House, 2014) Balavijayalakshmi J; Manju S; Lavanya S
In recent years, the research on semiconductor nanoparticles has stimulated much interest because of their unique optical and electrical properties. The nanosized semiconductor crystallites could produce optical properties which are different from bulk materials. Among the semiconductor nanoparticles, Zinc Sulphide is an important II–VI semiconductor material researched extensively because of its wide range of applications in electroluminescence devices, phosphors, light emitting displays and optical sensors. Semiconductor nanoparticles doped with transition metal ions have attracted much attention because of their luminescent properties. Hence an attempt is made to synthesize cupric chloride doped zinc sulphide nanoparticles. The synthesized nanoparticles are subjected to Xray diffraction to calculate the average nano-crystalline size using Debye – Scherrer formula and are found to be 2nm. The morphological analysis of the sample is studied using Scanning Electron Microscope. The UV-Visible spectrophotometer shows the absorption edge of the nanoparticles in range 292 to 261 nm. A FT-IR spectrum confirms the characteristic ZnS vibration peaks.