Anodic behaviour of the mercury electrode in aqueous solution of 1,10-phenanthroline: The role of adsorption and nucleation processes

Abstract

The anodic dissolution of the mercury electrode in 1,10-phenanthroline (phen) aqueous solution has been investigated by polarographic and voltammetric methods. The adsorption processes affecting the entire mechanism of oxidation and the complex formation have been observed and analysed introducing the random adsorption model (Frumkin isotherm) and the nucleation-growth collision model. The results suggest the occurrence of different surface structures of phenanthroline itself (the ligand) as well as of the product of the oxidative process, [Hg(phen) 2] 2+, upon varying the ligand concentration in the bulk.