COLL 403 |
| Vertically aligned carbon nanofibers (VACNFs) are a novel form of carbon with high stability and extremely high surface area of edge-plane graphite, suggesting they should be an excellent support for electrocatalysis. We have investigated the electrochemical properties of redox-active molecules grafted onto VACNFs as a model system for tethered electrocatalysis. Electrochemical impedance spectroscopy was used to investigate the impact of an attached molecular layer and tethered ferrocene molecules as a function of frequency and potential. Cyclic voltammetry and potential step methods were used to extract electron-transfer rates, and compare the electron transfer rates of ferrocene attached to VACNF with gold and glassy carbon planar surfaces. Electron transfer rates can be correlated with characteristics of the substrate using valence band spectroscopy to find the density of states. These results provide insight into the role of the substrate and organic monolayers in controlling the rates of molecular electrocatalysis at nanostructured electrodes. |
|
Interfacial Electron Transfer and Solar Energy Conversion: From Molecules to Nanomaterials
2:00 PM-5:40 PM, Wednesday, April 9, 2008 Morial Convention Center -- Rm. 226, Oral
Division of Colloid & Surface Chemistry |