Nanocrystalline CdS with different morphologies and particle sizes was obtained via a simple hydrothermal reaction between Cd(NO3)(2)center dot 4H(2)O and thioglycolic acid (TGA) at relatively low temperature. Products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) spectroscopy, photoluminescence spectroscopy (PL). Fourier transform infrared (FT-IR) spectra. and thermogravimetric-differential thermal analysis (TG-DTA). The effect of reactant concentration, molar ratio of TGA to the cadmium nitrate, temperature and reaction time on the morphology, particle sizes and phase of nanocrystalline CdS products has been investigated. (C) 2008 Elsevier B.V. All rights reserved.