Optical Layout and Endstation Concept for the Enhanced Liquid Interface Spectroscopy and Analysis (ELISA) Beamline at BESSY-II

Abstract

Liquid-vapor and liquid-solid interfaces drive numerous important processes in the environment and technology, such as the sequestra-tion of CO 2 by the oceans, the uptake and release of trace gases by aerosol droplets, the corrosion of metals, and reactions in electrochemical energy conversion and storage devices. Our understanding of the physical and chemical properties of liquid interfaces under realistic en-vironmental and operating conditions on the molecular scale still falls short of what has been achieved for solid-vapor interfaces over the past decades. This limitation hampers the development of, e.g., more precise climate models and electrochemical devices with increased efficiency. The main reason for this situation is the often greater difficulty in (1) the preparation of liquid interfaces (compared to solids) with controlled properties and (2) their investigation with high interface specificity under realistic conditions. This is partly due to the spatial fluctuations in the position of the interface and the fast diffusion from the interface into the bulk and vice versa (liquid-vapor), as well as