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arXiv · 1807.01250

Apparatus for dosing liquid water in ultrahigh vacuum

Jan Balajka·Jiri Pavelec·Mojmir Komora·Michael Schmid·Ulrike Diebold
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Abstract

The structure of the solid-liquid interface often defines function and performance of materials in applications. To study the interface at the atomic scale, we extended an ultrahigh vacuum (UHV) surface-science chamber with an apparatus that allows to bring a sample in contact with ultrapure liquid water without exposure to air. In this process, a sample, typically a single crystal prepared and characterized in UHV, is transferred into a separate, small chamber. This chamber already contains a volume of ultrapure water ice, whose vapor pressure is reduced to UHV range by cooling it to cryogenic temperatures. Upon warming, the ice melts and forms a liquid droplet, which is deposited on the sample. First experiments carried out on rutile TiO2(110) single crystals using this apparatus exhibit unprecedented purity, as tested by X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). These results enabled to separate the effect of pure water from the effect of low-level impurities present in the air. Other possible uses of the setup are discussed.

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Jan Balajka, Jiri Pavelec, Mojmir Komora, Michael Schmid, Ulrike Diebold. 2018-07-03. Apparatus for dosing liquid water in ultrahigh vacuum. https://doi.org/10.1063/1.5046846

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