Improved atomistic first-principles description of structures and processes at electrochemical electrode/electrolyte interfaces

• Applicant: Professor Dr. Axel Groß
• Subject Area: Theoretical Chemistry: Molecules, Materials, Surfaces
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 428022078

• Final Report Year: 2023

Final Report Abstract

In this project, we indeed achieved an improved first-principles description of structures and processes at electrochemical electrode/electrolyte interfaces. By running extensive and numerically demanding ab initio molecular dynamics simulations under potential control, we were able to elucidate crucial structural features of electric double layers at the interface between a metal electrode and an aqueous electrolyte, for example the change of the orientation of water molecules and the portion of strongly bound water molecules as a function of the electrode potential. Another very interesting result is the identification of the highly dynamical nature of the water molecules in the electric double layer. It is true that the still high numerical effort associated with the AIMD simulations prohibits their use as a routine tool to elucidate of a broad class of electrochemical interfaces. However, these simulations are necessary in order to provide benchmarks for more approximate methods, such as semiclassical methods which we also addressed in this project. Ideally, the AIMD simulations should also be coupled with thermodynamic integration routines to derive reaction mechanisms and free energy barriers at electrochemical interfaces. In fact, we are continuing to perform AIMD simulations to elucidate further details of electric double layers at water-metal interfaces, but also to address fundamental questions with respect to the driving force for the formation of electric double layers at electrochemical interfaces. Particularly the role of specifically adsorbed anions and non-specifically adsorbed cations in electrocatalytic reaction mechanisms needs to be explored. Hence there is still a high demand for further well-chosen AIMD simulations of electrochemical electrode/electrolyte interfaces.

Publications

• Diffusion on a Crowded Surface: kMC Simulations. The Journal of Physical Chemistry C, 124(28), 15216-15224.
  Sakong, Sung; Henß, Ann-Kathrin; Wintterlin, Joost & Groß, Axel
  
• Influence of Local Inhomogeneities and the Electrochemical Environment on the Oxygen Reduction Reaction on Pt-Based Electrodes: A DFT Study. The Journal of Physical Chemistry C, 124(50), 27604-27613.
  Sakong, Sung; Mahlberg, David; Roman, Tanglaw; Li, Mengru; Pandey, Mohnish & Groß, Axel
  
• Water structures on a Pt(111) electrode from ab initio molecular dynamic simulations for a variety of electrochemical conditions. Physical Chemistry Chemical Physics, 22(19), 10431-10437.
  Sakong, Sung & Groß, Axel
  
• Ab Initio Simulations of Water/Metal Interfaces. Chemical Reviews, 122(12), 10746-10776.
  Groß, Axel & Sakong, Sung
  
• Structure of PtRu/Ru(0001) and AgPd/Pd(111) surface alloys: A kinetic Monte Carlo study. Chemical Physics, 555, 111428.
  Mahlberg, David; Sakong, Sung & Groß, Axel
  
• The structure of the electric double layer: Atomistic versus continuum approaches. Current Opinion in Electrochemistry, 33, 100953.
  Sakong, Sung; Huang, Jun; Eikerling, Michael & Groß, Axel
  
• Comparing Ab Initio Molecular Dynamics and a Semiclassical Grand Canonical Scheme for the Electric Double Layer of the Pt(111)/Water Interface. The Journal of Physical Chemistry Letters, 14(9), 2354-2363.
  Huang, Jun; Zhang, Yufan; Li, Mengru; Groß, Axel & Sakong, Sung
  
• Diffusion of O Atoms on a CO-Covered Ru(0001) Surface─A Combined High-Speed Scanning Tunneling Microscopy and Density Functional Theory Study at an Enhanced CO Coverage. The Journal of Physical Chemistry C, 127(15), 7197-7210.
  Illner, Hannah; Sakong, Sung; Henß, Ann-Kathrin; Groß, Axel & Wintterlin, Joost