Stoichiometric effects on optical properties of cadmium sulphide quantum dots

Author

Chaure, S. ; Chaure, N.B. ; Pandey, R.K. ; Ray, A.K.

Author_Institution

Dept. of Mater., Univ. of London, London

Volume

1

Issue

3

fYear

2007

fDate

6/1/2007 12:00:00 AM

Firstpage

215

Lastpage

219

Abstract

Size quantised cadmium sulphide (CdS) nanocrystalline thin films with different particle sizes and stoichiometric ratios were successfully grown on indium tin oxide substrates using an aqueous synthetic route. The effect of cadmium (Cd) to sulphur (S) ratio on the optical properties of CdS nanocrystalline films was investigated using EDAX, UV-vis spectroscopy, photoluminescence and Raman spectroscopy. A satisfactory stoichiometric condition was achieved for 0.13 M concentration of thiourea whereas concentrations in the range of 1-1.2% of mercaptoethanol capping agents produced values much smaller than Wannier exciton diameter for CdS grain sizes, leading to quantum confinement. Photoluminescence emission bands and Raman peaks were analysed for the physical understanding of optimum growth of CdS quantum dots.

Keywords

II-VI semiconductors; Raman spectra; X-ray chemical analysis; cadmium compounds; grain size; nanostructured materials; nanotechnology; particle size; photoluminescence; semiconductor quantum dots; semiconductor thin films; stoichiometry; ultraviolet spectra; visible spectra; wide band gap semiconductors; CdS; EDAX; Raman spectroscopy; UV-visible spectroscopy; Wannier exciton; cadmium sulphide quantum dots; grain sizes; indium tin oxide substrates; mercaptoethanol capping agents; nanocrystalline thin films; optical properties; particle sizes; photoluminescence; quantum confinement; stoichiometric effects; thiourea;

fLanguage

English

Journal_Title

Circuits, Devices & Systems, IET

Publisher

iet

ISSN

1751-858X

Type

jour

DOI

10.1049/iet-cds:20070048

Filename

4273062