Structural characterization, optical properties, and improved solubility of carbon nanotubes functionalized with Wilkinson's catalyst

Oxidized carbon nanotubes have been reacted with Wilkinson's complex. It has been found that the Rh metal coordinates to these nanotubes through the increased number of oxygen atoms, forming a hexacoordinate structure around the Rh atom. The reaction process increases oxidized nanotube solubility in DMSO (> 150 mg/L) as well as to a certain extent in DMF and THF. The functionalization process results in exfoliation of larger bundles of SWNTs and may select for the presence of distributions of smaller-diameter tubes. Optical data on the derivatized adducts suggest the possibility of interesting charge-transfer behavior across the metal-nanotube interface. An application has been made of this system as supports for homogeneous catalysis.