ELLIPSOMETRIC AND ELECTROCHEMICAL CHARACTERIZATION OF THE NUCLEATION OF MERCURY ON GLASSY-CARBON

In previous papers on the nucleation and growth of mercury droplets on an inert substrate, the connection between the optical parameters and the population and size of the nuclei has been established. Some new results are presented allowing a test of both the electrochemical nucleation theory and the optical theory. There is excellent agreement between the nucleation densities determined independently by the two methods. The optical results moreover are very sensitive to another parameter, the size dispersion in the nuclei, which cannot be obtained with certainty by electrochemical techniques. The ellipsometric technique is therefore a powerful one for obtaining nuclear populations independently of electrochemical theory. Some results are also given for electrochemical growth of solid nuclei, suggesting that the technique may be of wider applicability than just to liquid metals. © 1990.