Formation and spectroscopic characterization of nearly mono-dispersed Cds nanocrystals

Using the organic solvent method, nearly mono-dispersed CdS nanocrystals were obtained in liquid paraffin. The CdS nanocrystals in tetrahedron shape capped with the hydrophobic surfactants in nanometer scale can be assembled to a close-packed mono-layered structure. The CdS nanocrystals with different sizes have been prepared by changing the reaction conditions such as the concentrations of cadmium precursor and sulfur precursor, the initial ratio of Cd:S precursors and the pH value of reaction system. The UV-visible absorption and photoluminescence show the quantum confinement effect clearly. The time-resolved photoluminescence spectra have also been examined. (C) 2004 Elsevier B.V. All rights reserved.