Shape selective growth of CdS one-dimensional nanostructures by a thermal evaporation process.

CdS one-dimensional nanoforms such as nanowires, nanoribbons, network-like nanowires, pearl necklace type nanowires, helical-like nanowires, and nanowire arrays were formed on Si substrates by a simple thermal evaporation route. The shapes of the one-dimensional CdS nanoforms were controlled by varying the experimental parameters such as temperature and position of the substrates. Formation of the CdS one-dimensional nanoforms was initiated by the Au catalyzed vapor-liquid-solid technique, whereas the vapor-solid process played a crucial role in defining the shapes of the nanoforms. Different optical characterizations such as optical absorbance, photoluminescence, and Raman spectroscopy were adopted to explore the physical and structural quality of these CdS nanoforms.