Structure of cadmium sulfide nanoparticle micelle in aqueous solutions

The structure of cadmium sulfide (CdS) micelle in stable aqueous solution of ethylenediaminetetraacetic acid was determined by dynamic light scattering, small-angle X-ray scattering and neutron scattering. The micelle aggregate is a single CdS nanoparticle with an average size of about 3 nm, the nanoparticle organic shell and the solvation shell are about 1 nm and 5 nm thick, respectively. These parameters were confirmed by the scanning semi-contact atomic force microscopy and powder X-ray diffraction studies of dry micelle cores isolated by high-speed centrifugation. The CdS micelle was correctly described by a simple double-shell model and was found to possess the structure corresponding to CdS quantum dots.