Stabilization of ZnS Nanoparticles in Micellar Dispersion of Cetyltrimethylammonium Bromide

ZnS nanoparticles were precipitated in micellar dispersions of cetyltrimethylammonium bromide (CTAB). ZnS nanoparticles and cetyltrimethylammonium (CTA+) ions formed positively charged ZnS-CTA micelles with the mode zeta potential of 35 mV. The ZnS-CTA micelles were simulated by molecular modelling that confirmed the formation of positive CTA+ bilayers on the ZnS surface. The large agglomerates of the ZnS-CTA micelles were observed by the dynamic light scattering (DLS) method and electron transmission microscopy (TEM). The size of the ZnS nanoparticles of about 5 nm was estimated from their band-gap energy obtained from UV spectra and electron transmission micrographs. The relationship between zeta potentials (ξ) and hydrodynamic sizes (d) was found as ξ = 641/d - 5.9.