Volume 40, Issue 3 (May 2012)
Solvothermal Synthesis of High Yield CdS Nanowires in Ethylenediamine
High yield CdS nanowires were synthesized by a solvothermal method using thiourea and cadmium nitrate tetrahydrate as precursors in ethylenediamine. The products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and UV-vis absorption spectroscopic techniques. XRD pattern indicates that the product is the hexagonal wurtzite CdS phase. SEM images show that the product is highly uniform CdS nanowires, and TEM images indicate that the diameter of the nanowires is about 50 nm and the length is up to several micrometers. Selected area electron diffraction (SAED) pattern reveals the as-prepared CdS nanowires’ single crystals with a preferential growth direction of (001). According to the experiments, the mechanism of the growth of CdS nanowires is discussed. The UV-vis absorption spectrum is shown to blueshift compared with that of bulk CdS due to the quantum size effect.