Raman scattering for the size of CdSe and CdS nanocrystals and comparison with other techniques

The sizes of the ensembles of CdSe regular nanocrystals (RNCs), CdSe magic-sized nanocrystals (MSNCs), and CdS RNCs were investigated by Raman scattering. The nanocrystal ensembles were synthesized via wet-chemistry approaches. The size distribution increases from CdSe MSNCs (2.26 nm), to CdSe RNCs (3.52 nm), and to CdS RNCs (3-8 nm and 4-10 nm). The sizes derived from Raman spectra are compared with those from other characterization tools such as UV/vis spectroscopy and transmission electron microscopy (TEM). The present study suggests that Raman scattering is an alternative and reliable technique for the determination of nanocrystal size and size distribution. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved.