ON THE ROLE OF SURFACE-ACTIVE AGENTS IN THE NUCLEATION STEP OF METAL ELECTRODEPOSITION ON A FOREIGN SUBSTRATE

The effect of surface active agents on the thermodynamics and kinetics of electrochemical nucleation has been analysed on the basis of the c lassical and atomistic theories of phase formation. The theoretical pr edictions were compared with experimental results obtained by studying the nucleation kinetics of mercury on platinum in both the absence an d the presence of potassium nitrate, which proved to be a surface acti ve agent with respect to the bulk mercury phase. The overpotential dep endence of the stationary nucleation rate was measured at different po tassium nitrate concentrations. It was shown that surface active agent s which change the properties of the new bulk phase may not significan tly affect the state of small clusters during the process of nucleus f ormation.