Electrochemical study of multiple states of chemisorption of atoms at metal surfaces

Electrochemical methods provide a sensitive way of studying adsorbed species at metals in contact with a solution. For such species as H, metal atoms, OH and O, direct information can be obtained at submonolayer coverages on (a) energies of adsorption of the chemisorbed species; (b) the lateral interactions involved in the adlayer and (c) the heterogeneous kinetics of the adsorption and desorption processes. In the potential‐sweep perturbation method, kinetic parameters for surface reactions can be obtained which characterize the reaction independently of knowledge of real surface area and hence give a true measure of electrocatalytic properties of a surface. An important feature, of great interest in surface science, is the resolution by electrochemical methods of multiple states of chemisorption of atoms on metal surfaces below monolayer coverage, even on single crystal surfaces. The electrochemical and optical (reflectance spectroscopy) study of H at Pt surfaces in various electrolytes is described as an example of this type of behavior.