Table of Contents
ISRN Optics
Volume 2012, Article ID 621908, 8 pages
http://dx.doi.org/10.5402/2012/621908
Research Article

Luminescence and Morphological Kinetics of Functionalized ZnS Colloidal Nanocrystals

Research Laboratory, Department of Physics, Maulana Azad National Institute of Technology, Bhopal 462051, India

Received 22 November 2011; Accepted 10 January 2012

Academic Editors: A. S. Gouveia-Neto, J. Jeong, A. V. Kir'yanov, D. Poitras, and J. S. Sanghera

Copyright © 2012 Prabha Sana et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper reports functionalized zinc sulphide (ZnS) semiconductor nanocrystals (quantum dots, approx., 2.5 nm) which are an important building block in self-assembled nanostructures. ZnS is functionalized by organic stabilizer Thio glycolic acid (TGA). The samples have been synthesized by colloidal technique at relatively low temperature (below 100°C) at an atmospheric pressure of 10−3 torr. Manganese (Mn) doping ions have been incorporated (doped) in ZnS host lattice and observed its effect on growth morphology and optical properties of ZnS colloidal nanocrystals. By XRD, SEM, TEM, and PL, the obtained cubic phase nanosized TGA-capped ZnS materials were characterized. The morphology of ZnS obtained at different temperatures are analyzed by SEM. The crystallite size of the ZnS nanoparticles was estimated from the X-ray diffraction pattern by using Scherrer’s formula (approximately 2.5 nm) which is confirmed by TEM. The estimated bandgap value of ZnS NC’s by ( 𝛼 β„Ž ́ 𝜐 )2 versus β„Ž ́ 𝜐 plot was 4.89 eV. Gaussian fitting curve in photoluminescence (PL) spectra indicated room temperature emission wavelength range from 300 to 500 nm in undoped and Mn-doped ZnS, with different emission peak intensities, and suggested the wide band emission colours in visible and near UV region which has wider applications in optical devices.