AVS 49th International Symposium
    Nanotubes: Science and Applications Topical Conference Monday Sessions
       Session NT-MoA

Paper NT-MoA3
Strategies for Carbon Nanotube Functionalization

Monday, November 4, 2002, 2:40 pm, Room C-209

Session: Nanotubes: Chemical Functionalization, Sensors
Presenter: S. Wong, SUNY at Stony Brook
Authors: S. Wong, SUNY at Stony Brook
S. Banerjee, SUNY at Stony Brook
Correspondent: Click to Email
Understanding the chemistry of single-walled carbon nanotubes (SWNTs) is critical to rational manipulation of their properties. In one set of experiments, raw and oxidized SWNTs have been reacted with metal-containing molecular complexes. One of the molecular complexes studied was Vaska's compound. It has been found that Ir coordinates to these nanotubes by two distinctive pathways. With raw nanotubes, the metal attaches as if the tubes behaved as electron-deficient alkenes. With oxidized nanotubes, the reaction occurs by coordination through the increased number of oxygen atoms, forming a hexacoordinate structure around the Ir atom. Another compound analyzed was Wilkinson's complex. It has been found that the Rh metal similarly coordinates to these nanotubes through the increased number of oxygenated species. The functionalization reaction, in general, appears to significantly increase oxidized nanotube solubility in DMF (in the case of Vaska's) and in DMSO (with Wilkinson's). The derivatization process results in exfoliation of larger bundles of SWNTs and may select for the presence of distributions of smaller diameter tubes. An application has been made of this system as supports for homogeneous catalysis. In another set of experiments, oxidized SWNTs have been reacted with cadmium selenide nanocrystals (quantum dots) as well as with titanium dioxide nanocrystals to form nanoscale heterostructures, characterized by transmission electron microscopy and infrared spectroscopy. Based on the types of intermediary linking agents used, we have demonstrated a level of control over the spatial distribution of nanocrystals on these tubes. Optical data on the derivatized adducts suggest the possibility of interesting charge transfer behavior across the nanocrystal-nanotube interface.