Surfactant- and temperature-controlled CdS nanowire formation

A solution-based synthesis of temperature-controlled CdS nanowires free from metal catalysts by using a mixture of surfactants was reported. The Transmission Electron Microscopy (TEM) images of CdS nanorods at 280°C show that the highly stable zinc blend structures form elongated structures with a nearly mono-dispersed lateral dimension. The X-Ray Diffraction (XRD) pattern of the elongated nanowires prepared at 320°C shows the diffraction peaks matching the wurtzite CdS standard pattern. The anisotropic growth of the nanocrystals is found to be due to the high monomer concentration after the nucleation stage. The luminescence peaks around 455 nm originates from the band edge of the as-prepared CdS nanorods and nanowires. The broad band emission from 525 nm extended to the region of near infrared arises from the defect states of CdS nanocrystals.