The objective of the current research is to synthesize CdS, ZnS nanocrystals through a two phases-method were quantum dots moved from the aqueous phase to the organic one after proper coating of the particles by decylamine. The UV-visible spectra of CdS dots suspended in toluene presented very sharp peaks in the range of 364-370 nm and confirmed the presence of CdS. ZnS quantum dots absorbed light in the 400-430 nm range. The sharpness in the absorption peak for CdS dots suggests a highly monodisperse suspension of synthesized nanocrystals. According to UV-Vis information, the crystal size of CdS could be estimated at 3.5 nm. Based on our experimental work, a Cd/S mole ratio of 0.78 and a SNTA concentration of 0.25 M were considered optimum synthesis conditions. PL spectra for CdS and ZnS are show blue shift in emission peak for ZnS dots with increasing decylamine volumes suggests the drop in crystal size.
Journal: TechConnect Briefs
Volume: 4, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 4
Published: May 20, 2007
Pages: 340 - 343
Industry sector: Advanced Materials & Manufacturing
Topics: Nanoparticle Synthesis & Applications