Fabrication of graphitic carbon nanostructures and their electrochemical applications

New methods to fabricate nanometer sized structures will be a major driving force in transforming nanoscience to nanotechnology. There are numerous examples of the incorporation of nanoscale structures or materials enhancing the functionality of a device. Graphitic carbon is a widely used material in electroanalysis due to a number of advantageous properties such as wide potential window, low cost, mechanical stability, and applicability to many common redox systems. In this thesis, the fabrication of nanometer sized graphitic carbon structures is described. These structures were fabricated by using a combination of electron-beam lithography (EBL) and pyrolysis. EBL allows for the precise control of shape, size and location of these carbon nanostructures. The structure and electrochemical reactivity of thin films of the pyrolyzed material is initially examined. The methodology to fabricate nanosized carbon structures and the structural and electrical characterization of the nanostructure is presented.;The nanometer sized carbon structures fabricated in this work are being applied as nanoelectrodes. For nanoband structures, we observe a limiting current plateau which is characteristic of radial diffusion to cylindrical ultramicroelectrodes. Their voltammetric behaviour shows good agreement with classical theoretical predictions. Both carbon film and nanoband electrodes have been used as substrates for metal electrodeposition. The size and morphology of the deposited Au particles depends greatly on the substrate. On the nanoband electrodes, the Au particles exhibit a multi-branched or dendridic morphology. Their size and surface area are much larger than those electrodeposited on the carbon film electrode under the same conditions. The surface enhanced Raman spectroscopy (SERS) properties of the gold deposited on the nanobands was studied. A high enhancement in Raman intensity for a molecular layer on the nanoband supported gold is observed.