In recent years, there has been significant progress made in the
modeling of electrochemical interfaces and electrocatalytic processes
from first principles (1). However, in most of the computational
studies, the influence of the electrochemical environment has not
explicitly been into account. Thus the role of the explicit presence
of the electrolyte, the correct equilibrium electrode coverage of ions
from the solution and/or the influence of varying electrode potentials
on electrocatalytic processes still need to be assessed.
In this contribution, recent attempts to address the equilibrium
coverage of hydrogen (2,3) and halides (4) on metal electrodes will be
presented. The presence of the aqueous electrolyte has been taken into
account modeling water layers either implicitly through a polarizable
medium (2) or explicitly in ab initio molecular dynamics runs (3).
The calculations confirmed experimental observations that electrode
surfaces can exhibit a high coverage - as a function of the electrode
potential - of either cations or anions. The adsorption
of ions can thus alter the properties of the electrode surface
significantly (3). Recent attempts to include the electrochemical
environment in a first-principles description of the electro-oxidation
of methanol on Pt(111) will be presented.
(1) S. Wang et al., Phys. Chem. Chem. Phys. 2011, 13, 20760.
(2) S. Sakong, M. Naderian, K. Mathew, R. G. Hennig, and A. Gross,
J. Chem. Phys. 2015, 142, 234107.
(3) T. Roman and A. Gross, Catal. Today. 2013, 202, 183.
(4) F. Gossenberger, T. Roman, and A. Gross, Surf. Sci. 2015, 631, 17.