A1 Journal article (refereed)
Grand Canonical Rate Theory for Electrochemical and Electrocatalytic Systems I : General Formulation and Proton-coupled Electron Transfer Reactions (2020)

Melander, M. M. (2020). Grand Canonical Rate Theory for Electrochemical and Electrocatalytic Systems I : General Formulation and Proton-coupled Electron Transfer Reactions. Journal of the Electrochemical Society, 167(11), Article 116518. https://doi.org/10.1149/1945-7111/aba54b

JYU authors or editors

Publication details

All authors or editors: Melander, Marko M.

Journal or series: Journal of the Electrochemical Society

ISSN: 0013-4651

eISSN: 1945-7111

Publication year: 2020

Volume: 167

Issue number: 11

Article number: 116518

Publisher: Electrochemical Society

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1149/1945-7111/aba54b

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/73407

Abstract

Electrochemical interfaces present a serious challenge for atomistic modelling. Electrochemical thermodynamics are naturally addressed within the grand canonical ensemble (GCE) but the lack of a fixed potential rate theory impedes fundamental understanding and computation of electrochemical rate constants. Herein, a generally valid electrochemical rate theory is developed by extending equilibrium canonical rate theory to the GCE. The extension provides a rigorous framework for addressing classical reactions, nuclear tunneling and other quantum effects, non-adiabaticity etc. from a single unified theoretical framework. The rate expressions can be parametrized directly with self-consistent GCE-DFT methods. These features enable a well-defined first principles route to addressing reaction barriers and prefactors (proton-coupled) electron transfer reactions at fixed potentials. Specific rate equations are derived for adiabatic classical transition state theory and adiabatic GCE empirical valence bond (GCE-EVB) theory resulting in a Marcus-like expression within GCE. From GCE-EVB general free energy relations for electrochemical systems are derived. The GCE-EVB theory is demonstrated by predicting the PCET rates and transition state geometries for the adiabatic Au-catalyzed acidic Volmer reaction using (constrained) GCE-DFT. The work herein provides the theoretical basis and practical computational approaches to electrochemical rates with numerous applications in physical and computational electrochemistry.

Keywords: electrochemistry; thermodynamics; quantum chemistry; density functional theory; theoretical research

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2020

JUFO rating: 1