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Detection of Superoxide Anion Oxygen Reduction Reaction Intermediate on Pt(111) by Infrared Reflection Absorption Spectroscopy in Neutral pH Conditions.

ABSTRACT: In this work, in situ external infrared reflection absorption spectroscopy (IRRAS) is successfully employed for the detection of intermediate species in the oxygen reduction reaction (ORR) mechanism on a flat and well-defined Pt surface. Superoxide anion species (O₂^-) are detected on the Pt(111) surface in an O₂-saturated solution with a NaF/HClO₄ mixture with pH 5.5 by the observation of a O-O vibration band at ca. 1080 cm^-1. The observation of O₂^- without the use of any other additional method of signal enhancement is possible because in these experimental conditions O₂^- is the main ORR-generated intermediate and its reactivity is limited in this pH. This leads to the accumulation of O₂^- near the Pt surface, facilitating its identification.

SUBMITTER: Briega-Martos V

PROVIDER: S-EPMC8460065 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Detection of Superoxide Anion Oxygen Reduction Reaction Intermediate on Pt(111) by Infrared Reflection Absorption Spectroscopy in Neutral pH Conditions.

Briega-Martos Valentín V Cheuquepán William W Feliu Juan M JM

The journal of physical chemistry letters 20210204 6

In this work, in situ external infrared reflection absorption spectroscopy (IRRAS) is successfully employed for the detection of intermediate species in the oxygen reduction reaction (ORR) mechanism on a flat and well-defined Pt surface. Superoxide anion species (O2-) are detected on the Pt(111) surface in an O2-saturated solution with a NaF/HClO4 mixture with pH 5.5 by the observation of a O-O vibration band at ca. 1080 cm-1. ...[more]

PMID: 33539102

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