Cadmium sulfide (CdS) nanocrystalline structures were grown through the solvothermal method at various temperatures (100, 120, 160, and 200 degrees C) for 7 h using ethylenediamine as the solvent. Two different CdS nanostructures were prepared: nanosheets were prepared at 100 and 120 degrees C and nanowires at 160 and 200 degrees C. The nanowire diameter ranged a few tens of nanometers, and the length reached several micrometers. The grown nanosheets and nanowires had a hexagonal wurtzite crystalline structure, as estimated from the X-ray diffraction pattern analysis. The growth direction of the nanowires grown at 160 and 200 degrees C was along < 001 >. The optical band gaps of the CdS nanosheets prepared at 100 and 120 degrees C were 3.25 and 2.42 eV, respectively, and 2.55 and 2.59 eV for the nanowires prepared at 160 and 200 degrees C, respectively. The photoluminescence spectra of the prepared nanostructures were analyzed. Results revealed that emission peak location and intensity depend on structure type and morphology. A single sharp emission peak at 480 nm was observed for the CdS nanowire grown at 200 degrees C, which was close to the absorption band edge. (C) 2012 Elsevier B.V. All rights reserved.