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Your search keyword '"Devi, K. Nomita"' showing total 2 results
Start Over Author "Devi, K. Nomita" Topic cadmium sulfide
2 results on '"Devi, K. Nomita"'

1. Optical and Structural Properties of Thermally Evaporated CdS Thin Films.

Author

Singh, Ch. Shyam, Devi, K. Nomita, and Sarma, H. N. K.

Subjects
*CADMIUM sulfide, *OPTICAL properties, *THIN films, *X-ray diffraction, *TRANSMISSOMETERS, *REFRACTIVE index, *POLYCRYSTALS
Abstract

Cadmium sulphide thin films were deposited by the vacuum evaporation technique onto well clean glass substrate held at 200 °C. The films have been annealed, in air, at two different temperatures, 300 °C and 350 °C. X-ray diffraction studies confirmed the polycrystalline hexagonal CdS phase formation. The structural parameters such as lattice parameter, crystallite size, dislocation density and strain have been evaluated. The transmittance and absorbance are measured at normal incidence, in the spectral range 500nm-1100nm. The transmittance data analysis indicates a direct band gap ranging from 2.49eV-2.28eV. Refractive index of the films has been evaluated in the wavelength λ = 600nm. [ABSTRACT FROM AUTHOR]

Published
2011
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2. STRUCTURAL AND OPTICAL CHARACTERIZATION OF PVA CAPPED CADMIUM SULPHIDE NANOPARTICLES BY CHEMICAL COPRECIPITATION METHOD.

Author

DEVI, L. SUJATA, DEVI, K. NOMITA, SHARMA, B. INDRAJIT, and SARMA, H. NANDAKUMAR

Subjects
*CADMIUM sulfide, *SEMICONDUCTOR nanocrystals, *POLYVINYL alcohol, *OPTICAL properties of semiconductors, *PRECIPITATION (Chemistry), *CRYSTAL structure, *X-ray diffraction, *SEMICONDUCTOR films, *EVAPORATION (Chemistry)
Abstract

CdS nanoparticles have been synthesized by chemical co-precipitation method using PVA as a capping agent. Structural characterization of the as synthesized CdS nanoparticles were performed by X-ray diffraction (XRD) study which showed hexagonal structure with average crystallite size of 11 nm and lattice constants a=4.106 Å, c=6.637 Å. Optical characterization of nanocrystalline thin films prepared by Vacuum Evaporation Method from the synthesized powder were done by Photoluminescence spectroscopy and UVVisible absorption spectroscopy. UV-Visible absorption spectrum showed blue shift in absorption edge with respect to bulk CdS. The photoluminescence spectrum of the CdS film exhibited green emission band with a maximum at 528 nm. Radius of the synthesized CdS nanoparticle has been evaluated from the absorption spectrum by using the effective mass approximation formula. [ABSTRACT FROM AUTHOR]

Published
2012

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