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Hydrogen-Induced Step-Edge Roughening of Platinum Electrode Surfaces.

ABSTRACT: Electrode surfaces may change their surface structure as a result of the adsorption of chemical species, impacting their catalytic activity. Using density functional theory, we find that the strong adsorption of hydrogen at low electrode potentials promotes the thermodynamics and kinetics of a unique type of roughening of 110-type Pt step edges. This change in surface structure causes the appearance of the so-called "third hydrogen peak" in voltammograms measured on Pt electrodes, an observation that has eluded explanation for over 50 years. Understanding this roughening process is important for structure-sensitive (electro)catalysis and the development of active and stable catalysts.

SUBMITTER: McCrum IT

PROVIDER: S-EPMC6844181 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Hydrogen-Induced Step-Edge Roughening of Platinum Electrode Surfaces.

McCrum Ian T IT Bondue Christoph J CJ Koper Marc T M MTM

The journal of physical chemistry letters 20191023 21

Electrode surfaces may change their surface structure as a result of the adsorption of chemical species, impacting their catalytic activity. Using density functional theory, we find that the strong adsorption of hydrogen at low electrode potentials promotes the thermodynamics and kinetics of a unique type of roughening of 110-type Pt step edges. This change in surface structure causes the appearance of the so-called "third hydrogen peak" in voltammograms measured on Pt electrodes, an observation ...[more]

PMID: 31618039

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