Characterization of Au/CdTe nanocomposites prepared by electrostatic interaction

Au/CdTe nanocomposites were prepared by electrostatic interaction between oppositely-charged gold (Au) and cadmium telluride (CdTe) nanoparticles. Au and CdTe nanoparticles were stabilized by 4-(dimethylamino)pyridine (DMAP) and 3-mercaptopropionic acid to develop positive and negative charges on their surfaces in aqueous solutions, respectively. The red shifts of the surface plasmon absorptions with the increase of Au content indicate that the sizes of the nanocomposites expanded due to the complex formation. Mixing ratio of Au and CdTe nanoparticles controls the structure of the resulting composites effectively. Moreover, the sizes and shapes of the mixed nanoparticles are important parameters for the formation of metal/semiconductor nanocomposites. The Au/CdTe nanocomposites were characterized by small angle X-ray scattering technique (SAXS), transmission electron microscopy (TEM), cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS).