Perspective on experimental evaluation of adsorption energies at solid/liquid interfaces

Abstract

Almost 15 years ago, first papers appeared, in which the density functional theory (DFT) was used to predict activity trends of electrocatalytic reactions. That was a major contribution of computational chemistry in building the theory of electrocatalysis. The possibility of computational electrocatalyst design had a massive impact on the way of thinking in modern electrocatalysis. At the same time, substantial criticism towards popular DFT models was developed during the years, due to the oversimplified view on electrified interfaces. Having this in mind, this work proposes an experimental methodology for quantitative description of adsorption energies at solid/liquid interfaces based on the Kelvin probe technique. The introduced approach already gives valuable trends in adsorption energies while in the future should evolve into an additional source of robust values that could complement existing DFT results. The pillars of the new methodology are established and verified experimentally with very promising initial results.

Electrocatalysis Beyond 2020: How to Tune the Preexponential Frequency Factor

“…Most of the properties are defined in Eq. 1. except: E act -activation energy; A -preexponential factor; [39,40] E MÀ H -intermediate bond strength energy, that is linked with intermediate adsorption energy; E MÀ H2O -energy consumed for metalÀ water interaction or water bilayer reconstruction during HER; [41] A lat.vib -hypothetical contribution of individual and collective lattice vibrations to effective collisions; A tun -hypothetical contribution of proton tunneling to product formation. In order to summarize briefly the scheme given in Figure 3, we could note the following: 1) overpotential at defined current density is determined by exchange current (close to equilibrium kinetic parameter) and Tafel's slope (far from equilibrium kinetic parameter).…”

Determining the Complete Stability of Calcite Kink Sites: Real vs Ideal

“…The reason for the above difference in the two sets of kink stabilities has actually been understood for a long time, though it is rarely discussed explicitly in computational studies of ion binding at solid–liquid interfaces for minerals (in contrast to other fields, such as electrocatalysis), namely, an interfacial potential shifts the free energy of the ions in the solution phase relative to the solid. When using pathway-based free energy determinations, the ion has to cross the interface, whereas in alchemical methods when the ion transforms from being in the solid to a completely separate solution, this contribution is absent.…”

Determining the Complete Stability of Calcite Kink Sites: Real vs Ideal

“…The reason for the above difference in the two sets of kink stabilities has actually been understood for a long time, 55 though is rarely discussed explicitly in computational studies of ion binding at solid-liquid interfaces for minerals (in contrast to other fields, such as electrocatalysis 56 ), namely an interfacial potential shifts the free energy of the ions in the solution phase relative to the solid. When using pathway-based free energy determinations, the ion has to cross the interface, whereas in alchemical methods when the ion transforms from being in the solid to a completely separate solution then this contribution is absent.…”