Preparation and characterization of CdS and ZnS nanosized particles obtained by the inert gas evaporation method

In the present paper we describe the preparation conditions to obtain CdS a nd ZnS nanocrystalline samples by the gas phase condensation method The mat erials are constituted in both cases by very homogeneous spherical particle s with a mean particle diameter of 8 and 15 nm respectively for the ZnS and CdS samples. Characterization has been carried out by X-ray diffraction (X RD) and transmission electron microscopy (TEM). High resolution images show that under certain conditions samples can be obtained with single crystall ite grains of homogeneous size. Relative band-gap values have been determin ed from the UV-vis absorption spectra and correlated with quantum size effe cts for very small crystallite sizes in the nanostructured powders. (C) 199 9 Acta Metallurgica Inc.