Chemically Modified Electrodes: Determining Thin Film Thickness

Chemical modification of electrodes is key in developing electrochemical sensors that can detect various substances in our environment, such as hydrazine, which the EPA has classified as a compound that causes liver and kidney problems. As the need for these sensors increases, new techniques and compounds will be used in the chemical modification of electrodes. This research focused primarily on the chemical modification of platinum electrode surfaces via electropolymerization of a ruthenium complex, [Ru(5-phenNH2)](PF6)2, which is known to detect hydrazine. The characterization of this multilayered film is accomplished with cyclic voltammetry and Rutherford backscattering spectrometry (RBS); the thickness of the Ru thin film was determined using RBS. It was found that the thickness of the film and the amount of material immobilized on the electrode surface was directly dependent on the concentration of the ruthenium complex as well as the number of cycles of electropolymerization undergone. The RBS method has proven to be a very useful and effective means of determining thin film thickness