To a Theory of Electrocatalysis for the Hydrogen Evolution Reaction: The Hydrogen Chemisorption Energy on the Transition Metal Alloys within the Anderson–Newns Model

Abstract

Estimates of the energy of chemisorption of hydrogen (ECH) on a number of alloys of transition metals that are of interest from the viewpoint of a theory of electrocatalysis are made within the Anderson–Newns model. As a simplest example, the behavior of ECH as a function of the position of the Fermi level of a system for nickel containing admixtures of simple metals is studied in a fixed-band approximation. As alternative examples, where this approximation is not fulfilled, a calculation of ECH on tungsten carbide and a Pd1 – xAg x alloy is performed. It is shown that agreement between calculated ECH and observed ECH is reached in the case of an Ni1 – xCu x alloy after taking into account mutual influence of processes of adsorption and segregation on the alloy surface. Dependence of rates of a number of electrochemical reactions on the composition and electronic structure of alloys is discussed for all the alloys considered and a comparison with experiment is performed.