Perovskite oxides possess great potential for many applications, such as (photo)catalysis, fuel cells,
electronics or spintronics. The bottleneck for their practical use lies in detailed understanding of the
materials surfaces at the atomic scale: There is an inherent problem with the stability of perovskites
at operating conditions, and a detailed understanding of their interaction with the ambient
environment is currently lacking. We have recently pioneered how to prepare well-defined surfaces
of two cubic perovskites, KTaO3 and SrTiO3, suitable for surface-science studies [Science 359, 572
(2018)]. These surfaces represent a perfect starting point for applying the analytical techniques of
surface science and studying the detailed interaction of these materials with molecules from the
external atmosphere. Understanding these interactions is essential for optimizing catalytic reactions
in applications like fuel cells or photocatalytic light harvesting. Further, the bulk-terminated surfaces
used in this work provide access to bulk properties of the materials, such as special electronic states
or ferroelectricity. Detailed understanding of these properties aims towards opening new routes in
oxide electronics and enabling new generation of electronic devices operating beyond binary logic.