The Problem of the Influence of the Nature of Metal on the Electrocatalytic Process and Its Solution Based on a Combination of the Vacancy Thermodynamic Model and Equilibrium Statistical Thermodynamics

• Published in: Protection of metals and physical chemistry of surfaces Vol. 60; no. 1; pp. 1 - 17
• Main Authors: Andreev, Yu. Ya, Terentyev, A. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.02.2024; Springer Nature B.V
• Subjects: Atomic properties; Catalysts; Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper; Corrosion and Coatings; Electrode polarization; Energy; Energy conversion efficiency; Energy distribution; Free energy; Gibbs equations; Gold; Heat of formation; Hydrogen evolution; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; Metallic Materials; Palladium; Physicochemical Processes at the Interfaces; Statistical analysis; Statistical thermodynamics; Surface energy; Surface layers; Thermodynamic models; Tribology; active centers; statistical distribution of vacancies; electrocatalysis; surface energy of a crystal face; atomic vacancies
• ISSN: 2070-2051; 2070-206X
• DOI: 10.1134/S2070205124701405

Using the vacancy thermodynamic model and the formula for the surface energy of a metal face (1998), the authors assume that the number of (atomic) vacancies in the surface layer (SL) in the form of active centers of the catalyst is determined by the conversion of surface energy metal into the energy of formation of surface vacancies (SVs) under the influence of temperature and (or) electrode polarization. In this regard, in addition to the known thermal vacancies, another source of vacancies has been identified—the internal surface energy of the face of fcc metals , to convert the energy of vacancies into the energy with the greatest efficiency. Using the Gibbs equation—the dependence of the probability of distribution on the external energy—in calculations, it was found that the logarithm of the number of SVs increases with increasing in the series of metals Ag, Al, Au, Ni, Cu, Pd, and Pt. Using an updated scale of absolute surface potentials for Me crystal polarization, a formula is proposed for calculating the atomic hydrogen evolution overpotential on Me-catalyst , where is reversible potential , as a function of pH of the environment, and is the reversible potential of the metal catalyst.