Photoluminescent properties of new quantum dot nanoparticles/carbon nanotubes hybrid structures

The preparation of multi-wall carbon nanotubes (CNTs) and sulfide core–shell CdSe@ZnS quantum dot nanoparticles based hybrid materials is reported here. Photoluminescent measurements were carried out on two kinds of QD-CNT heterostructures. Indeed, strong oxidation of CNTs led to shorter nanotubes opened at their ends, allowing the grafting of mercaptotriethoxysilane whereas the generation of diazonium salts in presence of pristine nanotubes led to the functionalization of the whole lateral surface of the nanotubes and was achieved for the first time to anchor sulfide QD nanoparticles to thiol groups borne by carbon nanotubes. In both cases, we observed an important decrease in the photoluminescence peak, highlighting strong interactions between QDs and CNTs even when QDs were anchored to CNTs through a covalent link. Finally, we demonstrated that the morphology of the nanohybrids is governed by the surface chemistry of CNTs, leading to interesting hybrid precursors for photovoltaic applications.