In situ quantum dot growth on multiwalled carbon nanotubes.

The generation of nanoscale interconnects and supramolecular, hierarchical assemblies enables the development of a number of novel nanoscale applications. A rational approach toward engineering a robust system is through chemical recognition. Here, we show the in situ mineralization of crystalline CdTe quantum dots on the surfaces of oxidized multiwalled carbon nanotubes (MWNTs). We coordinate metallic precursors of quantum dots directly onto nanotubes and then proceed with in situ growth. The resulting network of molecular-scale "fused" nanotube-nanocrystal heterojunctions demonstrates a controlled synthetic route to the synthesis of complex nanoscale heterostructures. Extensive characterization of these heterostructures has been performed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, UV-visible spectroscopy, and X-ray diffraction (XRD).