A simple ultraviolet photochemical reduction synthetic approach to preparing US nanocrystals with different morphologies is described. Sodium dodecyl sulfate (SDS) was used as soft template for the chemical synthesis of US nanocrystals in a mixture solution at room temperature. It was found that the magnetic force stirring and the volume proportions of C2H5OH and H2O had marked influences on the morphology of US nanocrystals (such as spherical, acicular-like, rod-like and worm-like shapes). The formation of US is via precipitation of Cd2+ ions with the homogeneously released S2- ions from decomposition of thioacetamide under ultraviolet icradiation source. X-ray diffraction (XRD), scanning electron microscopy (SEM) and the ultraviolet-visible (UV-vis) absorption spectra were employed to characterize the products. This novel method is expected to produce various semiconductor nanocrystals with potential applications in the fields of materials science and photovoltaic cells, etc. (c) 2006 Elsevier B.V. All rights reserved.