Spectroelectrochemical Study of Carbon Nanotube and Indium Oxide Thin Films

Two related spectro-electrochemical experiments were performed. In the first experiment voltages applied to a single walled carbon nanotube (SWCNT) thin film induced changes in the transmittance spectrum of the film. The changes are attributed to a voltage-modulated shift in the Fermi level of the nanotubes in the film. From this study the intrinsic doping level of the semiconducting carbon nanotubes was also determined. In the second experiment, an Indium Oxide thin film was subjected to varying voltages to change the film’s free carrier electron density and thereby also modulate the film’s transmittance. A spectroelectrochemical cell with high chemical resistance was designed for use in these experiments. Spectroelectrochemistry is a field of study that combines spectroscopy with electrochemistry. Spectroelectrochemistry can provide valuable information about thin films, such as the effects of different applied voltages on the optical transmittance of the thin film. Aqueous electrolyte is commonly used in many electrochemical applications