Florian MAIER1, Hans-Peter STEINRÜCK1, Leonhard WINTER1
1Friedrich-Alexander-Universität Erlangen-Nürnberg, Chair of Physical Chemistry II , Erlangen, Germany
About one decade ago, one of us published a perspective “Surface science goes liquid” describing some possibilities of investigating surfaces and interfaces of vacuum-stable liquids with classical surface science tools under ultrahigh vacuum (UHV) conditions.[1]
Since then, new experimental concepts and setups have been developed by others and by our group that consider the special requirements for handling ionic liquids (ILs) in vacuum in order to push the boundaries of surface science experiments further.
In this presentation, we would like to review along key showcases some of our experimental developments (including non-published pitfalls), which are dedicated to derive quantitative composition of the outer surfaces of liquids using angle-resolved X-ray photoelectron spectroscopy (ARXPS),[2] to prepare ultrathin layers in vacuum using IL-adapted physical vapour deposition (IL-PVD),[3] to image deposited layers with sub-molecular resolution employing non-contact AFM,[4] to investigate potential screening effects at electrode-electrolyte interfaces with XPS,[5] to probe IL surfaces with a supersonic molecular beam in order to derive sticking coefficients,[6] and to use pendant and sessile drops in UHV measuring surface and interface tension values under ultra-clean and well-defined conditions.[7]