Investigations into the Role of Modifiers for Entrapment of Hydrides in Flow Injection Hydride Generation Electrothermal Atomic Absorption Spectrometry as Exemplified for the Determination of Germanium

Bo Hilligsøe, Jens Enevold Thaulov Andersen, Elo Harald Hansen

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    Pd-conditioned graphite tubes, placed in the furnace of an atomic absorption spectrometry instrument, are used for entrapment of germane as generated in an associated flow injection system. Two different approaches are tested with the ultimate aim to allow multiple determinations, that is, introduction of the modifier as a liquid Pd-salt solution, and use of electrolytically Pd-precoated tubes. While the former treatment resulted in satisfactory analytical performance, although requiring separate regeneration of the tubes prior to each sampling sequence, the electrolytically precoated tubes did not function at all. This in turn led to a closer investigation as to the function of Pd in entrapping hydrides and releasing the analyte. Based on evaluation of the behaviour of the two types of tubes, and supplemented by scanning tunnelling microscopy studies of tubes with and without modifier and treated in different manners, it is suggested that the role of Pd primarily is that of a catalyst, that the electrochemically precoated tubes do not allow the germane to be entrapped during the short contact time available, and that the liquid Pd-modifier do not affect the graphite tubes per se, yet must be injected prior to each analytical cycle.
    Original languageEnglish
    JournalJournal of Analytical Atomic Spectrometry
    Volume12
    Issue number5
    Pages (from-to)585-588
    ISSN0267-9477
    Publication statusPublished - 1997

    Keywords

    • Palladium modifier
    • Electrolytically pre-coated
    • Role of modifier
    • Hydride determination
    • Graphite tube
    • Scanning tunnelling microscopy
    • Germane
    • Flow injection

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