Growth of CdS nanosheets and nanowires through the solvothermal method

Cadmium sulfide (CdS) nanocrystalline structures were grown through the solvothermal method at various temperatures (100, 120, 160, and 200°C) for 7h using ethylenediamine as the solvent. Two different CdS nanostructures were prepared: nanosheets were prepared at 100 and 120°C and nanowires at 160 and 200°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°C was along . The optical band gaps of the CdS nanosheets prepared at 100 and 120°C were 3.25 and 2.42eV, respectively, and 2.55 and 2.59eV for the nanowires prepared at 160 and 200°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 480nm was observed for the CdS nanowire grown at 200°C, which was close to the absorption band edge. ► CdS nanosheets and nanowires were prepared through the solvothermal method. ► The crystalline structure of the grown nanosheets and nanowires was hexagonal. ► Nanowire growth direction was along . ► The optical band gaps of the nanosheets and nanowires were blue-shifted. ► At high temperature, the nanowires showed strong single PL emission.