Investigations on Chemically Capped CdS Nanoparticles

CdS nanoparticles of various sizes were synthesized through a wet chemical method including passivation by organic capping molecules (Thioglycerol). The desired particle sizes were achieved by adjusting the concentration and pH of the reactants. Our experiments reveal some advantages of wet chemical synthesis in ethanol solvent compare to aqueous solvent such as smaller sizes with narrow size distribution. We discuss these through some differences in TG action and electrostatic forces between colloids.

Optical absorption spectroscopy was used primarily to monitor the process of particle formation, and to measure the band gaps and particle sizes. Photoluminescence spectra show low surface trap in ethanol solvent compare to aqueous solvent. XRD spectra yield information about the crystal structure of the particle core and sizes of the particles. In this report, for a typical sample, the preferable structure for CdS nanoparticles is hexagonal structure in ethanol synthesis.

Keywords:

• cadmium sulfide nanoparticles
• aging effect
• capping agent action
• hexagonal structure

The financial support of the Research Deputy of Guilan University is kindly appreciated. We wish to thank Dr. N. Taghavinia and his colleges (Institute for Nanoscience and Nanotechnology, Sharif University of Technology) for helpful discussions.