The reversible one-electron oxidation of ferrocene in acetonitrile at arrays of microdisk electrodes, linear microelectrodes and very thin ring electrodes prepared with a uniform glass real or a layer of epoxy resin between the conductor and the glass has been investigated in the ms and sub-ms time domains by a range of transient electrochemical techniques and chronocoulometry. The data are compared with that from a conventional-sized disk electrode (0.8 mm radius) and illustrate the significant advantages of using ultra-microelectrodes with transient voltammetric techniques provided that the electrodes are correctly constructed. The responses of the transient electrochemical techniques of differential pulse, square wave and ac voltammetry, as well as chronocoulometry are strongly influenced by irregularities originating in the construction of inlaid microelectrodes of microscopic dimensions of less than 1 μm. Imperfectly prepared electrodes with cracks in the glass seal or with thick sealing layers of epoxy resin exhibit undesirable background currents which prevent their use for measurements in short time regimes.
|Number of pages||10|
|Journal||Journal of Electroanalytical Chemistry and Interfacial Electrochemistry|
|Publication status||Published - 25 Feb 1987|