A simple route to synthesize carbon-nanotube/cadmium-sulfide hybrid heterostructures and their optical properties

Multi-walled carbon nanotube/cadmium sulfide hybrid heterostructures were easily synthesized by employing a thermal decomposition of thioacetamide as a sulfide-ion source in an aqueous regime. The resulting cadmium-sulfide phase is comprised of a zinc-blende structure of spherical polycrystalline nanoparticles (cadmium-sulfide nanoclusters) with the subunits of ca. 15nm, deposited on the nanotube Surface. The formation of the cadmium-sulfide nanoparticles with zinc-blende structure (cubic crystal) Suggests that the local concentrations of reacting ion species in the vicinity of the nanotube surface are different from those in the reaction Solution. The cadmium-sulfide nanoparticles are comprised of a stoichiometrically ideal chemical-composition ratio (cadmium: sulfur = 1:1.02) of cadmium and sulfur with the valence states of +2 and -2, respectively. The optical responses of the cadmium-sulfide phase for Ultraviolet-visible light and photoluminescence spectroscopes show the proper size-effect and inherent optical properties of the cadmium-sulfide nanoparticles. (C) 2009 Elsevier Inc. All rights reserved.