Theoretical analysis of the influence of surface defects on the reactivity of hypophosphite ions

Masahiro Kunimoto, Akira Otomo, Nana Takahashi, Hiromi Nakai, Takayuki Homma

    Research output: Contribution to journalArticle

    4 Citations (Scopus)

    Abstract

    To elucidate the influence of surface defects, such as steps, on the oxidation of a reducing agent that is used in the electroless deposition process, we theoretically analyzed the reaction behavior of hypophosphite ion around the defect using density functional theory calculations. The reason why we chose the hypophosphite ion is that it is a typical reducing agent and reacts through a universal reaction mechanism. In this analysis, we focused on the dehydrogenation reaction, which is the rate-determining step in the oxidation pathway. Pd and Cu surfaces were chosen as the metal surfaces, because they exhibit completely different catalytic activity from each other, both experimentally and theoretically. Our calculations showed that the surface defect stabilized the final state of dehydrogenation on both Pd and Cu surfaces, which indicates that the defect accelerates the oxidation of the hypophosphite ion. In the final state of dehydrogenation, dissociated hydrogen adsorbs on the hollow site, which appears on the slope of the defect. More detailed analyses of the final state indicate that the stabilization effect by the surface defect originates from the highly efficient interactions between the dissociated hydrogen and the slope. The molecular orbital structure on this slope is distorted, which leads to high electron density around the slope that enables the highly efficient interactions between the hydrogen and the slope.

    Original languageEnglish
    Pages (from-to)785-791
    Number of pages7
    JournalElectrochimica Acta
    Volume113
    DOIs
    Publication statusPublished - 2013 Dec 15

    Fingerprint

    Surface defects
    Dehydrogenation
    Hydrogen
    Reducing Agents
    Reducing agents
    Ions
    Oxidation
    Defects
    Defect density
    Electroless plating
    Molecular orbitals
    Density functional theory
    Carrier concentration
    Catalyst activity
    Stabilization
    Metals

    Keywords

    • Density functional theory
    • Electroless deposition
    • Hypophosphite ion
    • Surface defects

    ASJC Scopus subject areas

    • Electrochemistry
    • Chemical Engineering(all)

    Cite this

    Theoretical analysis of the influence of surface defects on the reactivity of hypophosphite ions. / Kunimoto, Masahiro; Otomo, Akira; Takahashi, Nana; Nakai, Hiromi; Homma, Takayuki.

    In: Electrochimica Acta, Vol. 113, 15.12.2013, p. 785-791.

    Research output: Contribution to journalArticle

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