GROWTH AND CHARACTERIZATION OF CdS AND CdS:Ag LUMINESCENT QUANTUM DOTS DISPERSED IN SOLUTION

A fast-chemically capping method in aqueous solution was developed to synthesize CdS and CdS:Ag luminescent nanoparticles and particles with sizes between 2-4 nm. The achieving of well-dispersed and narrow-sized particles in colloidal solution and also, high stability of them using mercaptoethanol (ME) as a capping agent was established. Quantum confinement effect was observed in UV-vis absorption as well as in PL spectra. PL spectroscopy also showed green emission and Ag dopants caused a faster energy transfer between CdS inter-bands. XRD patterns exhibited that both cubic and hexagonal phases exist in solutions. Ultimately, TEM images captured from QDs displayed the shapes of nanoclusters which are almost spherical.