Preparation And Properties Of Cds, Cdse Nanocrystals Study

As a kind of very important photoelectric materials ,CdS and CdSe nanoparticles have drawn much attention recently. Because of its potential applications, a variety of synthesis have been developed. Depending on the preparing method used, the diameter, uniformity, and purity, and the properties of nanoparticles are also different accordingly.This dissertation studied on the preparation of nano-sized CdS and its photocatalytic properties. A novel solid-state method for the preparation of the CdS nanoparticles at the room temperature has been developed. The CdS nanoparticles were analyzed by FT-IR, XRD, DTG-DTA, XPS, TEM, UV-vis and fluorescence spectroscopy. the results indicated that the surfaces of the CdS nanoparticles were modified with sodium thioglycolate and thus they were water-dispersive. The mean particle size was about 3~4nm. UV-vis spectra showed that there is a blue-shift in the absorption of CdS nanoparticlesPoly(styrene-alt-maleic anhydride) capped CdSe nanoparticles were prepared at room temperature. XRD, TEM, UV-Vis were used to characterize the final products. For the PSM-capped CdSe nanocrystals, the interaction between PSM and CdSe was studied and the growth process of CdSe nanocrystals was discussed. The results showed that particle size was about 3~4 nm.The photocatalytic activities of the prepared samples were evaluatedby decoloration reaction of methyl orange. The results of experimentation showed that nanocrystalline CdS had good photocatalytic activities in alkalescencing circumstance. The CdS nanoparticles modified Pt electrode has been fabricated and its electrocatalytic activity for the oxidation of p-benzenediol was investigated.