A new possibility of application of electron tunneling effects in electrochemical double layer structure investigations

Abstract

A new method has been developed for studying in situ the dependence of the electroresistance of films on the electrolyte composition and potential. The method consists of measuring the contact electroresistance between two identical metallic specimens periodically contacted in electrolyte under potentiostatic control, in particular between the walls of a fatigue crack in a sample cyclically loaded below the corrosion fatigue crack growth threshold. The sensitivity of the method is 10 −9 Ω and it can be used for all conducting materials in any electrolytes at normal and high temperatures and pressures in a wide region of potentials including the potentials of the intensive evolution of hydrogen or oxygen. The method allows one to determine electroresistance of films on metals during adsorption of water and anions, formation and destruction of hydride and oxide films, electrodeposition of metals and electrochemical incorporation of cations, to study the kinetics of these processes and their dependence on potential, activators and inhibitors of corrosion. The water adsorption potentials for 16 metals are defined which are proposed to characterize the hydrophility of metals. The possibility of STM application in electrochemical double-layer structure investigations is briefly discussed in connection with the scan rate of STM and oscillation frequency of the double-layer particles. Electron tunneling between macrocontacts through thin electrolyte layers is proposed to be useful for the investigation of the processes in the double layer.