Increased propensity of Iaq - for the water surface in non-neutral solutions: Implications for the interfacial behavior of H 3Oaq + and OHaq -

N. Ottosson, L. Cwiklik, J. Söderström, O. Björneholm, G. Öhrwall, P. Jungwirth

    Research output: Contribution to journalArticleScientificpeer-review

    17 Citations (Scopus)

    Abstract

    By a combination of surface-sensitive photoelectron spectroscopy and molecular dynamics simulations, we characterize the surface propensity of the iodide anion in aqueous solutions at acidic, neutral, and basic conditions (pH = 1, 6.8 and 13). In both experiments and simulations, an increased surface concentration of I- is found in non-neutral solutions. We interpret these findings in terms of I- surface coadsorption with hydronium at low pH and salting out of iodide by hydroxide from the bulk solution to the surface at high pH. The present study is thus in accord with the picture of a weak surface adsorption of hydronium and surface depletion of hydroxide, being in sharp contradiction with the interpretation of electrophoretic and titration measurements in terms of strong surface enrichment of OH-.

    Original languageEnglish
    Pages (from-to)972-976
    Number of pages5
    JournalJournal of Physical Chemistry Letters
    Volume2
    Issue number9
    DOIs
    Publication statusPublished - 5 May 2011
    Publication typeA1 Journal article-refereed

    ASJC Scopus subject areas

    • Materials Science(all)

    Fingerprint

    Dive into the research topics of 'Increased propensity of Iaq - for the water surface in non-neutral solutions: Implications for the interfacial behavior of H 3Oaq + and OHaq -'. Together they form a unique fingerprint.

    Cite this