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Tracking Electrical Fields at the Pt/H₂O Interface during Hydrogen Catalysis.

ABSTRACT: We quantify changes in the magnitude of the interfacial electric field under the conditions of H₂/H⁺ catalysis at a Pt surface. We track the product distribution of a local pH-sensitive, surface-catalyzed nonfaradaic reaction, H₂ addition to cis-2-butene-1,4-diol to form n-butanol and 1,4-butanediol, to quantify the concentration of solvated H⁺ at a Pt surface that is constantly held at the reversible hydrogen electrode potential. By tracking the surface H⁺ concentration across a wide range of pH and ionic strengths, we directly quantify the magnitude of the electrostatic potential drop at the Pt/solution interface and establish that it increases by ?60 mV per unit increase in pH. These results provide direct insight into the electric field environment at the Pt surface and highlight the dramatically amplified field existent under alkaline vs acidic conditions.

SUBMITTER: Ryu J

PROVIDER: S-EPMC6777043 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Tracking Electrical Fields at the Pt/H2O Interface during Hydrogen Catalysis.

Ryu Jaeyune J Surendranath Yogesh Y

Journal of the American Chemical Society 20190918 39

We quantify changes in the magnitude of the interfacial electric field under the conditions of H2/H+ catalysis at a Pt surface. We track the product distribution of a local pH-sensitive, surface-catalyzed nonfaradaic reaction, H2 addition to cis-2-butene-1,4-diol to form n-butanol and 1,4-butanediol, to quantify the concentration of solvated H+ at a Pt surface that is constantly held at the reversible hydrogen electrode potential. By trac ...[more]

PMID: 31433173

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