First-principles hydration free energies of oxygenated species at water-platinum interfaces

Author(s)
Ryosuke Jinnouchi, Ferenc Karsai, Carla Verdi, Georg Kresse
Abstract

The hydration free energy of atoms and molecules adsorbed at liquid-solid interfaces strongly influences the stability and reactivity of solid surfaces. However, its evaluation is challenging in both experiments and theories. In this work, a machine learning aided molecular dynamics method is proposed and applied to oxygen atoms and hydroxyl groups adsorbed on Pt(111) and Pt(100) surfaces in water. The proposed method adopts thermodynamic integration with respect to a coupling parameter specifying a path from well-defined non-interacting species to the fully interacting ones. The atomistic interactions are described by a machine-learned inter-atomic potential trained on first-principles data. The free energy calculated by the machine-learned potential is further corrected by using thermodynamic perturbation theory to provide the first-principles free energy. The calculated hydration free energies indicate that only the hydroxyl group adsorbed on the Pt(111) surface attains a hydration stabilization. The observed trend is attributed to differences in the adsorption site and surface morphology.

Organisation(s)
Computational Materials Physics
External organisation(s)
Toyota Central R&D Labs, VASP Software GmbH
Journal
Journal of Chemical Physics
Volume
154
No. of pages
8
ISSN
0021-9606
DOI
https://doi.org/10.1063/5.0036097
Publication date
03-2021
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics, 103006 Chemical physics
Portal url
https://ucris.univie.ac.at/portal/en/publications/firstprinciples-hydration-free-energies-of-oxygenated-species-at-waterplatinum-interfaces(74457017-4e31-4a8f-9649-4e8fbbc5dd2a).html