AVS 56th International Symposium & Exhibition
    Surface Science Thursday Sessions
       Session SS2-ThM

Paper SS2-ThM4
Interfacing Electrocatalytic Molecules with Vertically Aligned Carbon Nanofibers through Click Chemistry: An Approach to “Smart”, Highly Functional Nanostructures

Thursday, November 12, 2009, 9:00 am, Room N

Session: Electron Activated Molecular Interfaces
Presenter: E.C. Landis, University of Wisconsin, Madison
Authors: E.C. Landis, University of Wisconsin, Madison
R.J. Hamers, University of Wisconsin, Madison
Correspondent: Click to Email
Vertically Aligned Carbon Nanofibers are a unique form of nanoscale carbon comprised of graphene cups nested together to form a nanofiber. A unique feature of VACNFs is that they expose large amounts of graphene edge-planes along the nanofiber sidewalls. The high electron transfer rates associated with edge plane graphite suggest that VACNFs should be an excellent support for electrocatalysis. However, nanofibers alone lack the specificity often desired in electrochemical reactions. We have developed a method for covalently binding redox active molecules to the VACNF surface based on “click” chemistry as a pathway toward combining the high stability of VACNFs with the selectivity provided by molecular redox-active groups. This binding method creates a highly stable linkage of VACNFs to a ‘smart’ ligand with well defined redox properties. Using XPS, FTIR, and other surface analytical methods in conjunction with electrochemical measurements, we have investigated how the nanoscale structure of the fibers and the nature of the surface ligands impacts the surface chemistry and subsequent electron transfer processes. Our results demonstrate that the graphitic edge-plane sites of VACNFs play a key role in the chemical reactivity of VANCFs and in the subsequent electron-transfer processes on VACNFs functionalized with redox-active groups. These results demonstrate that VACNFs are a promising material for functional nanostructures using covalently tethered molecular catalysts.