The selective synthesis of single-crystalline CdS nanobelts and nanowires by thermal evaporation at lower teperature

摘要

CdS nanobelts and nanowires were successfully synthesized by simple thermal evaporation of CdS powder at a temperature as low as 650 deg C, using pure H_2 as a carrier gas. The morphology of the products could be conveniently controlled by adjusting the deposition parameters. Electron microscopy studies of the materials showed that the single-crystalline CdS nanowires have a diameter of 200 nm and a length of tens of micrometres, and the nanobelts are 100-200 nm in width, 30 nm in thickness and tens of micrometres in length. High-resolution transmission electron microscopy demonstrated that the nanobelts, which are different from the nanowires growing along the (0001) direction, have three types of growth direction: (2110), (0110) and (0001). It is demonstrated that a reductive carrier gas, such as hydrogen, plays an important role in the whole growth process of CdS nanowires and nanobelts.