Surface-Coated CdS Nanocrystals

CdS nanocrystals were prepared using a standard colloidal route (co-precipitation chemical reaction) whereas modulation of the optical and structural properties was realized via surface coating the nanocrystals with ethylene glycol molecules using an in situ procedure. The as-produced nanocrystals were characterized by X-ray diffraction, Raman spectroscopy, UV-absorption measurements and photoluminescence. The nanocrystal quality was revealed by the spectroscopic data, though the final product presents a mixture of both zinc blende (cubic) and wurtzite (hexagonal) phases. The X-ray data indicated that the concentration of the ethylene glycol used during the synthesis process modulates the nanocrystal size and the crystal phase of the end material.