A1 Journal article (refereed)
Cations Determine the Mechanism and Selectivity of Alkaline Oxygen Reduction Reaction on Pt(111) (2023)

Kumeda, T., Laverdure, L., Honkala, K., Melander, M. M., & Sakaushi, K. (2023). Cations Determine the Mechanism and Selectivity of Alkaline Oxygen Reduction Reaction on Pt(111). Angewandte Chemie, 62(51), Article e202312841. https://doi.org/10.1002/anie.202312841

JYU authors or editors

Laverdure, Laura
Honkala, Karoliina
Melander, Marko

Publication details

All authors or editors: Kumeda, Tomoaki; Laverdure, Laura; Honkala, Karoliina; Melander, Marko M.; Sakaushi, Ken

Journal or series: Angewandte Chemie

ISSN: 1433-7851

eISSN: 1521-3773

Publication year: 2023

Publication date: 20/11/2023

Volume: 62

Issue number: 51

Article number: e202312841

Publisher: Wiley-VCH Verlag

Publication country: Germany

Publication language: English

DOI: https://doi.org/10.1002/anie.202312841

Publication open access: Openly available

Publication channel open access: Partially open access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/92133

Web address of parallel published publication (pre-print): https://arxiv.org/abs/2205.00719

Abstract

The proton-coupled electron transfer (PCET) mechanism of the oxygen reduction reaction (ORR) is a long-standing enigma in electrocatalysis. Despite decades of research, the factors determining the microscopic mechanism of ORR-PCET as a function of pH, electrolyte, and electrode potential remain unresolved, even on the prototypical Pt(111) surface. Herein, we integrate advanced experiments, simulations, and theory to uncover the mechanism of the cation effects on alkaline ORR on well-defined Pt(111). We unveil a dual-cation effect where cations simultaneously determine i) the active electrode surface by controlling the formation of Pt−O and Pt−OH overlayers and ii) the competition between inner- and outer-sphere PCET steps. The cation-dependent transition from Pt−O to Pt−OH determines the ORR mechanism, activity, and selectivity. These findings provide direct evidence that the electrolyte affects the ORR mechanism and performance, with important consequences for the practical design of electrochemical systems and computational catalyst screening studies. Our work highlights the importance of complementary insight from experiments and simulations to understand how different components of the electrochemical interface contribute to electrocatalytic processes.

Keywords: oxidation-reduction reaction; reduction (chemistry); electrocatalysis; platinum; surface chemistry; electrochemistry

Free keywords: constrained DFT; electrocatalysis; energy conversion; kinetic isotope effects; Marcus theory

Fields of science: