Shape-controlled synthesis of polyhedral CdS fowerlike architectures and their optical properties

摘要

Fabrication of polyhedral CdS fower-like architectures have been achieved on a large scale through a mixed solvothermal method. The obtained CdS are characterized by X-ray diffraction, feld-emission scanning electron microscopy and transmission electron microscopy, and the results indicate that the CdS fower-like architectures with diameters of 1.5-2.0 μm are hexagonal wur tzite phase and are assembled by some pyramids with the bottom side length of about 440 nm, which have some crystallographic faces. A series of relevant experiments through altering experimental parameters, indicate that the temperature, star ting materials and solvent play key roles for the shape evolution of CdS fower-like architectures. The studies of optical proper ties for polyhedral CdS fower-like architectures indicate that the UV-vis spectroscopy shows a blue-shift absorption peak at 500 nm compared to that of bulk CdS, the photoluminescence spectroscopy shows an emission peak at 640 nm and another strong emission peak at 695 nm, which are believed to be attributed to excitonic emission and deep levels.